This Nanaimo Bar Cake takes the classic Canadian treat and transforms it into a delicious layer cake! Chocolate cake layers with a vanilla custard frosting and chocolate coconut crumble.
There’s a good chance you are probably reading this right now and thinking – what the heck is a Nanaimo bar?!
Rest assured, you are not alone. Unless you grew up in Canada or have a passionate Canadian in your life, you likely won’t have heard of this amazingly delicious treat. Those who do know it though, know that it is ubiquitous around here. You’ll be able to find Nanaimo bars in every grocery store and every local bakery across the country.
What is a Nanaimo Bar?
A Nanaimo bar is a no bake treat made of a chocolate graham cracker/coconut base (sometimes also with almonds), followed by a yellow custard filling and finally a layer of chocolate. According to Wikipedia, there seems to be a bit of controversy as to where the bar actually originated, but to avoid any potential wrath, I’m going to stick with saying it was in Nanaimo, BC.
Did you KNOW (and this is news to me) that you can do a self-guided tour in Nanaimo and try over 30 different variations of Nanaimo bars?? They have a map with all the delicious locations you can hit up. Amazing. That Nanaimo bar milkshake is calling my name.
Nanaimo bars are known for their signature yellow custard layer. There is really nothing like it. There’s also not much to it, to be honest. It’s basically butter, powdered sugar, and custard powder (which is what gives it that signature yellow color). I’ll fully admit that the only things I’ve ever used custard powder for are this cake and actual Nanaimo bars. I wish it came in a smaller container! It’s not a bank-breaker, but I don’t like to see things go to waste.
What can be used instead of custard powder?
I’m not sure how readily available custard powder is outside of Canada and the UK, but it doesn’t seem too hard to find, as both Amazon and Walmart seem to carry it. The main ingredient in custard powder is cornstarch, so you can try to replace it with that and increase the amount of vanilla for taste. You won’t be able to get that signature yellow color this way, but it would still be delicious.
Ideally though, use the custard powder if you can find it!
When making this Nanaimo Bar Cake, I ran through a few different options. My first plan was to incorporate the graham cracker crumbs and coconut right into the cake batter, but I nixed that for two reasons:
- This chocolate cake batter is very thin, so I imagined the coconut would just sink to the bottom.
- The graham cracker and coconut flavor would likely be lost in the rich chocolate cake.
Instead, I decided to do a crumble layer to make sure the flavor of that classic Nanaimo bar base came through, but also to add some texture.
I wanted the decoration of the cake to emulate a Nanaimo bar as much as possible, so I kept it simple — a naked cake so that you would see the layers of chocolate and custard, and a drippy chocolate ganache to evoke that top layer of the Nanaimo bar. If you wanted to, you could put some ganache between the layers too. I think that would be a nice addition, but I would double the ganache recipe if you plan to do that.
If you love Nanaimo bars as much as I do, you will love this Nanaimo bar cake! It’s basically a deconstructed Nanaimo bar with rich chocolate cake layers. What’s not to love?? For my non-Canadian friends, I really hope you will give this one a try. It is totally delicious, and you’ll wonder why Nanaimo bars haven’t infiltrated every part of the world yet.
Looking for more Chocolate Cake recipes?
- Peanut Butter Chocolate Cake
- French Silk Pie Cake (Copycat Deep n’ Delicious Chocolate Cake)
- Chocolate Strawberry Cake
- Mocha Chocolate Cake
Tips for making this Nanaimo Bar Cake
- The cake batter is very thin and rises a lot. Do not be alarmed by this!
- If you can’t find custard powder you can try to replace it with cornstarch and increase the amount of vanilla for flavor.
- For the crumble layer, use fine shredded coconut if you can find it, but it’s not critical.
- If you like, you can sprinkle more shredded coconut over the crumble layer when stacking the cake.
- For the ganache, I find that a good quality chocolate makes a huge difference. I use Callebaut because that’s what is available to me.
- To help ensure your cake layers bake up nice and flat, check out my Flat Top Cakes post!
Nanaimo Bar Cake
Ingredients
Dark Chocolate Ganache:
- 3 oz good quality dark chocolate
- 3 oz heavy cream
Chocolate Cake:
- 1 1/2 cup all-purpose flour
- 1 1/2 cups granulated sugar
- 3/4 cup Dutch-processed cocoa powder sifted
- 1 1/2 tsp baking soda
- 1 tsp baking powder
- 1 tsp salt
- 1/4 cup vegetable oil
- 3/4 cup buttermilk room temperature
- 3/4 cup hot water
- 2 large eggs room temperature
- 2 tsp vanilla extract
Chocolate Coconut Crumble:
- 3/4 cup graham cracker crumbs
- 1/4 cup fine shredded coconut unsweetened
- 2 Tbsp granulated sugar
- 1 Tbsp Dutch-processed cocoa powder
- 1 tsp black cocoa powder optional (for color)
- 1/4 cup unsalted butter melted
Vanilla Custard Frosting:
- 1 1/2 cups unsalted butter room temperature
- 4 cups powdered sugar sifted
- 1/4 cup custard powder
- 2 Tbsp heavy cream more if needed
- 1 tsp vanilla extract
Instructions
Dark Chocolate Ganache:
- Finely chop chocolate and place into a bowl. Bring cream just barely to a simmer and pour over chopped chocolate. Cover with plastic wrap and let stand 2 mins. Stir with a spatula until combined, smooth, and silky. Set aside to cool completely until thickened but still pourable. See notes.*
Chocolate Cake:
- Preheat oven to 350F, grease three 6″ round baking pans and dust with cocoa powder. Line bottoms with parchment.
- Place all dry ingredients into the bowl of a stand mixer fitted with a paddle attachment. Stir to combine.
- In a medium bowl whisk all wet ingredients (pour water in slowly as not to cook the eggs if very hot).
- Add wet ingredients to dry and mix on medium for 2-3 mins. Batter will be very thin.
- Pour evenly into prepared pans. I used a kitchen scale to ensure the batter is evenly distributed. Bake until a cake tester comes out mostly clean. A total of 35-40mins.
- Cool 10 minutes in the pans then turn out onto a wire rack to cool completely.
Chocolate Coconut Crumble:
- Preheat oven to 350F and line a baking sheet with parchment. Whisk all dry ingredients in a medium bowl. Pour in melted butter and stir until it begins to clump.
- Spread evenly on baking sheet and bake for 15mins. Cool completely before using on cake.**
Vanilla Custard Frosting:
- Prepare a stand mixer with a whisk attachment. Whisk butter until creamy, scraping bowl as needed.
- Reduce speed to low and add in powdered sugar 1 cup at a time until well blended, add custard powder. Increase speed to med and beat for 3 minutes.
- Add vanilla and 2 Tbsp cream and continue to whip on medium for 1 minute.
- Add more cream as needed until desired consistency is reached (I added all 4 Tbsp). Whip until the frosting is smooth and silky.
Assembly:
- Place one layer of cake on a cake stand or serving dish. Top with about 2/3 cup buttercream, spread evenly. Sprinkle some of the crumble on top. Repeat with remaining layers, but don’t sprinkle crumble on the very top layer.
- Frost and smooth the outside with a thin crumb coat (thicker on the very top). Chill for 20mins.
- Using a small spoon, place dollops of ganache around the top edges of the cooled cake, allowing some to drip down. Fill in the top of the cake with more ganache and spread evenly with an offset spatula.***
- Use a 1M tip to pipe dollops on top with remaining frosting and sprinkle some crumble in the middle.
Notes
** You will have some crumble leftover after using it in the cake. You can use this as a topping for ice cream or a crunch layer in another cake.
*** You may have some ganache left over.
Sharon says
Hi: This is so delicious! I would like to use 2/8inch pans. Should I double recipe? How long should I bake the cakes?
Olivia says
Hi Sharon! I would change the Servings to 16 and use those amounts. Baking time will be similar.
Anne says
Hi, the problem with that is then it says 2 2/3 eggs. Would you just do 3 eggs?
Olivia says
Hi Anne! To be precise I would crack an egg, whisk it lightly, weigh it and then use 2/3 of that. Or you can use this recipe instead which is specifically made for two 8″ pans. It’s slightly less dense though.
Merle says
I made this for my birthday cake. It was delicious and VERY rich, like Nanaimo Bars. My layers did not stick together well when cut. Next time I would also pipe a ring of frosting around the edge of the middle layers, before putting the crumbs in, to glue them together. My family were very impressed with the presentation and pronounced it delicious!
Olivia says
Hi Merle! So glad you loved it. Happy belated birthday!
Allyson says
This is a fantastic recipe! We don’t like a ton of icing on our cakes, so I reduced the custard frosting recipe to 2/3 and still had plenty to cover the cake. I used up some of the crumble on the bottom third of the cake and placed the ganache in a thick layer on top. Looked just like a giant Nanaimo bar and wow, was it ever delicious. If you like Nanaimo bars, you will love this cake!!!
Olivia says
Hi Allyson! So happy you loved it. Thanks so much for your feedback and tips! 🙂
Dottie says
This was so yummy! I didn’t have the right sized cake pans so I baked it on a 10 x 15 sheet pan for 30mins and cut out the circles using a template and this worked well! Because of the style of the cake it still looked nice even though a bit of crumb for into the outside icing. We put it in the fridge after the first day and we both preferred it cold because it was even more like the bars. Great flavours for all components! I might put ganache in the layers next time for a bit more of a chocolate kick!
Olivia says
Hi Dottie! I’m so happy you liked it. Thanks for the feedback!
Bonnie says
This is delicious! The chocolate cake is one of the best I have tasted. I did ‘paint’ the top of the layers with Kahlua (1/3 cup) prior to assembling which added another flavor layer. I won’t lie, it’s time consuming but the cake is very nice to look at and even better tasting. I’m a west coast Canadian girl snd have lived my life eating Nanaimo bars…this is great!
Olivia says
Hi Bonnie! I am so happy you loved this one 🙂 Thanks for your feedback!
Julie says
Hi Olivia,
I am so excited about this Nanaimo Cake, being a Canadian and all!
Can you please tell me how deep your 6 inch pans are? I found a pKg of 5, that says to use one cake mix. It’s for a rainbow cake, but they are super shallow.
Your help is greatly appreciated!
Happy baking!
Julie
Olivia says
Hi Julie! All my pans are 2″ deep, but 3″ will work too. I know the pans you mean. As long as they are a total of 6″ deep then I think it should work ok (though I’m not sure they are). Note that the batter here is very thin and rises a lot, so don’t fill your pans more than half full. That could be tricky with the super thin ones.
Julie says
Thank you so much for your reply Olivia 🙂
Yes, these shallow pans look like they’re better suited for an easy bake oven 😉
I was able to find some 3” deep, now let the baking begin! ….once they deliver 😀
Also, I’m a huge fan of the cake pan strips for even baking. I immerse them in cold water and then put them in the fridge until I’m ready to put the pans in the oven. Works like a charm every time!
Be well, and happy baking!
Julie
Olivia says
I love the cake strips too! I never thought about putting them in the fridge! Great idea. I’ll have to try that!
Julie says
Does the cake need to be refrigerated once made?
Mine turned out a little different than yours… the big taste test is tomorrow. 🤞
Olivia says
Hi Julie! It will be ok at room temperature for a couple days, but I tend to refrigerate mine.
Helen says
Is it possible to add chopped almonds , pecans or walnuts to the crumble like the nanaimo bar base?
Olivia says
Hi Helen! For sure! I think that would be a delicious addition. For ease, and the make sure the crumble isn’t too dry, I would probably just sprinkle the chopped nuts on top of the crumble when frosting the cake.
Shirley says
Hi I’ve read through the comments and prepping for the recipe, and I noticed the cake pans are only 6” – can I double this and use larger pans like 8”?
Olivia says
Hi Shirley! For three 8″ cake pans you can 1.5x the recipe.
Violet C says
Everyone loved this cake when I made it, just wondering but can you turn this one into cupcakes?!
Olivia says
Hi Violet! Yes for sure. All you need to do is reduce the baking time — start checking at 15mins or so. Don’t fill them more than half full because the batter rises a lot.
Sandra Hussey says
I made this cake for my daughter’s 23rd Birthday, everyone seen to like it. I am presently making your blueberry banana cake for my grandson 1st birthday 🙂
Olivia says
Hi Sandra! So happy everyone liked it. The Blueberry Banana one is delicious! I hope you love that too 🙂
Deborah beaton says
Thank you for this recipe. I made it for my grandchildren , it was lovely . Decorated the cake the same as the picture. It really looked impressive. Everyone loved it.
Olivia says
Hi Deborah! Yay! So happy everyone loved it 🙂
Dia says
Made this last year for a birthday and it was such a hit that my family finished the entire cake within one day – they aren’t cake fans so it was a bit of a shocker!!! I plan on making this cake again real soon but was wondering how much buttercream the vanilla custard frosting makes as my parents are coming over and I would like to make a healthier version by using whipping/heavy cream instead 😋 I know it wont be the same experience but there’s no harm in experimenting
Hope to hear from you soon,
Thank you 💖
Olivia says
Hi Dia! So happy you love this one. I’ve never measured it but I think this recipe makes about 3 cups of frosting or so.
Jane Doyle says
I grew up in the 1960’s with these bars being called New York Squares . My aunt introduced them to our family at a wedding shower and I’ve been making them ever since ! The recipe called for vanilla instant pudding instead of custard powder. It gives the yellow colour and vanilla flavour.
These have evolved into Nanaimo bars in my family as we are proud Canadians! Can’t wait to try this cake version of our favourite treat.
Olivia says
Hi Jane! Thanks for sharing some of your history with these. I hope you love the cake as much as I do 😀
Amanda says
This is actually the best cake that I have ever had. Seriously.
There were three things I did a little differently – instead of buttermilk in the chocolate cake, I used sour cream. And I added a full tablespoon of really fine espresso ground beans to help bring out more of the chocolate flavour. I also doubled the crust portion and put it on nice and thick in between the layers.
SOOO freaking amazing.
Thanks so much for this.
Olivia says
Hi Amanda! That is seriously high praise. I’m so happy you loved it 🙂
Pat says
I am confused? Why would cake not rise just because one changes the pan size? I have never heard of that. Just don’t understand response to the problem of not rising. She is a beauty.
Olivia says
Hi Pat! I’m not sure which comment you’re referring to. The cake should rise regardless, but if baked in too large a pan it will be very flat.
Darlene says
I haven’t tried this yet, but I am dying to make it happen. Another use for my custard powder and it’s cake! 😊
Just a suggestion for using the custard powder: trifles! There are so many seasonal variations that you could use up that whole tin in no time.
Olivia says
Great tip Darlene! Thank you 🙂 I hope you love this cake!
Brianna says
I have tried making this THREE TIMES and the cake batter has never risen. After the first failure I’ve made sure to test my baking soda AND baking powder, check the freshness of my eggs and I’ve followed each step exactly. Each time I’ve had to resort to using boxed cake mix and then assemble with the frosting, crumble and ganache. The assembled results have been a hit, but the cake bater never made it to the table.
Olivia says
Hi Brianna! Sorry to hear you’re having trouble with this one. The cake actually rises a LOT (doubles in size), so there must be something off. Are you at high elevation by chance?
Emmanuelle says
Hi, I made this cake this morning, and I knew my pans were bigger than 6″, so I had planned to double the batter.. But I forgot and the cakes didn’t rise at all. I redid the cake with a double recipe and now they rose a lot!
So maybe your problem was not enough batter for the size of your pans?
Ingrid says
I grew up on a farm and the local grocery store (in the 60s) didn’t have custard powder , we used vanilla pudding powder instant or the kind you had to cook. Worked fine
Olivia says
Hi Ingrid! I think that would give the traditional Nanaimo bar a slightly different flavour and color. It would still be delicious though 🙂
Whysper says
I have no clue how I stumbled on this page, but I thank the Google Gods that I did! I really wish I have not already added the cocoa powder to the custard I am about to make for my cake :/ I am in the middle of making a peanut butter and chocolate cake. Each layer edged in peanut butter buttercream and filled with chocolate custard. But I think I know what my next cake is going to be. I am thinking mint though. My favourite version of the Nanaimo bar. Thank you for the recipe, I can’t wait to try it!
Olivia says
Hi Whysper! Your cake sounds delicious! And thank you for the sweet comment. I hope you love this cake as much as I do.
Maggie says
Excellent cake (but the bars are yummier) Must use “Birds custard powder”
It is. a do again!
I live in Nanaimo BC Canada so I have to be careful who I serve this to. LOL
Mmm
Olivia says
Hi Maggie! So happy you liked my cake version of those delicious bars 😀