With layers of chocolate buttermilk cake and lots of vanilla buttercream, this cookies and cream cake will remind you of the ice cream flavor.
Nonstick cooking spray
1–3/4 cup granulated sugar
1–3/4 cup all-purpose flour
1 cup unsweetened cocoa powder
1–1/2 teaspoons baking powder
1–1/2 baking soda
1–1/2 teaspoons kosher salt
2 large eggs
1 cup buttermilk
1 tablespoon vanilla extract
1/2 cup canola oil
3/4 cup boiling water
4 sticks unsalted butter at room temperature
5–1/3 cups confectioners’ sugar
1/2 teaspoon kosher salt
2–1/2 teaspoons vanilla extract
2–1/2 tablespoons milk
15–20 chocolate sandwich cookies
For the cake, preheat the oven to 350 degrees F. Grease two 8-inch round cake pans with nonstick cooking spray and line the bottoms with parchment.
In a large bowl, whisk together the granulated sugar, flour, cocoa powder, baking powder, baking soda and salt. In a medium bowl, beat together the eggs, buttermilk, vanilla extract and oil. Fold the wet ingredients into the dry ingredients followed by the boiling water. Divide the batter between the prepared cake pans and bake for 28-30 minutes until a toothpick inserted in the center of the cake comes out clean.
Cool the cakes in their pans for 10 minutes before removing them and cooling completely on a wire rack. Peel off and discard the parchment.
For the frosting, in the bowl of a stand mixer fitted with the paddle attachment, beat the butter on low speed and slowly add the sugar followed by the salt, vanilla extract and milk. Increase the speed and mix for a few minutes until smooth and fully combined.
Put the cookies in a food processor or blender and grind into crumbs.
To put together the cake, use a serrated knife to trim the tops of the cakes if they are uneven. Using an offset spatula, frost the top of one of the layers and stack the other one on top. Frost the top of the cake followed by the sides. Press the cookie crumbs into the frosting to decorate the cake.