Recipe: Black Onyx Cake with Vanilla Bean Paste Frosting
This recipe yields a silky-smooth, moist cake. The cake is not too sweet, which makes the vanilla frosting a perfect pairing. We highly recommend the optional addition of maple extract in the frosting and maple sugar for dusting the finished cake.
- 3 cups milk
- 3 Tbsp. lemon juice
- 1 1/2 cups unsalted butter, softened
- 3 cups sugar
- 1 tsp. vanilla bean paste
- 5 eggs
- 3 1/3 cups cups all-purpose flour
- 1 tsp. kosher salt
- 3/4 cup black onyx cocoa powder
- 1/2 cup Dutch cocoa powder
- 1/2 cup unsalted butter, softened
- 4 cups confectioners’ sugar
- 2 tsp. vanilla bean paste
- 1/2 tsp. maple extract (optional)
- 4 to 6 Tbsp. milk
- 1 Tbsp. maple sugar (optional)
This recipe makes 2 (9- to 10-inch) Bundt cakes or round cakes for stacking. If using a round cake pan, make sure it has tall sides as the batter is thin and can overflow in a smaller cake pan.
For cakes: Preheat oven to 350 degrees. Mix milk with lemon juice and set aside; after 10 min. this mixture curdles/thickens into the equivalent of buttermilk. Beat butter, sugar and vanilla bean paste with an electric mixer until evenly blended. Add eggs one at a time until combined. Combine dry ingredients in a separate bowl and gradually add to butter mixture until combined. Add milk/lemon mixture until combined. Gradually increase speed to high and beat for 3 min., stopping to scrape sides of bowl as needed. Pour batter into 2 greased Bundt or cake pans and bake for 35 to 40 min. or until a toothpick comes out clean. Cool cakes completely before turning out and frosting.
For frosting: Beat butter, sugar, vanilla bean paste and maple extract (if using) with an electric mixer until evenly blended. Gradually add milk 1 Tbsp. at a time until desired consistency is reached. Less milk yields a spreadable frosting and more milk yields a pourable glaze. Frost cooled cakes and sprinkle with maple sugar (if using).