-
1
Preheat the oven to 350 degrees F. Brush two 9-inch-round cake pans with vegetable oil; dust with flour and tap out the excess.
-
2
Make the cake: Whisk the flour, cocoa powder, baking soda and salt in a medium bowl. Combine the granulated sugar, vegetable oil, buttermilk, eggs and vanilla in a large bowl; whisk until smooth. Whisk in the food coloring, then add the flour mixture and whisk until smooth.
-
3
Spread 3/4 cup batter in each of the prepared pans (you'll have a very thin layer of batter); set the remaining batter aside. Bake until a toothpick inserted into the center of a cake comes out clean and the top springs back when pressed, 16 to 18 minutes. Transfer to a rack and let cool about 5 minutes in the pans, then invert the cakes onto the rack to cool completely.
-
4
Meanwhile, cool the pans under cold water, then wipe clean. Brush with oil and dust with flour again. Repeat to make 2 more cake layers, using 3/4 cup batter for each, then repeat again. You will have 6 layers.
-
5
Make the frosting: Beat the cream cheese, butter and salt in a stand mixer fitted with the paddle attachment on medium-high speed until fluffy. Beat in the vanilla, then beat in the confectioners' sugar in three additions until smooth.
-
6
Put 1 cake layer on a serving plate and spread evenly with a scant 1 cup frosting. Repeat with the remaining 5 cake layers, then frost the top and sides of the cake with the remaining frosting in a thin layer (just enough so the nonpareils will stick). Refrigerate until the frosting is just set but still soft, about 10 minutes.
-
7
Put the cake (on the plate) on a rimmed baking sheet. Cover the top and sides completely with the nonpareils, reusing the ones that fall onto the baking sheet.
