These rich and buttery Mint Nanaimo Bars are a refreshing twist on a classic Canadian dessert featuring layers of chocolate coconut crust, minty custard buttercream filling, and chocolate on top.
LIne a 9x9-inch square baking pan with parchment paper or wax paper. Combine graham crumbs, coconut, powdered sugar, and cocoa powder. In a separate dish, melt the butter and chocolate chips together in the microwave in 15-second increments*, stirring between each increment. Add to the dry ingredients and mix until combined. Press firmly into the prepared pan and refrigerate while making the custard layer.
For the Custard:
Beat together softened butter, custard powder, powdered sugar, milk, peppermint extract, and food coloring using a handheld mixer starting on low and increasing to high as the mixture starts to come together. Beat on high speed for 1 minute or until fluffy. Using an offset spatula, gently spread the custard onto the chilled crust, being careful not to pull up the crust layer. Refrigerate while making the final layer.
For the Topping:
Melt the chocolate chips and butter together in the microwave in 15-second increments* or on the stovetop on low. Once the other layers have chilled slightly, gently spread the chocolate mixture on top of the custard layer. Chill for at least 2 hours before removing from the pan. Slice into 32 squares to serve. Enjoy!
Notes
If you dislike coconut, you may replace it with an equal measurement of finely chopped pecans, walnuts, or almonds.
Use unsalted butter with ¼ teaspoon of added salt to each ½ cup of butter.
While I have not tested it myself, I have heard that people have had success using cornstarch, powdered milk, or even French vanilla pudding mix in place of custard powder. Or you can buy custard powder from Amazon.
This natural food coloring is a great option if you are trying to avoid synthetic color.
Heating chocolate too quickly will cause the chocolate to "seize" and become lumpy and unpleasant in texture.
Store finished Nanaimo Bars in an airtight container in the refrigerator for up to 5 days.