Best-Ever Chocolate & Nutella Layer Cake
Super-moist, dark chocolate cake filled and frosted with satiny dark chocolate & Nutella sour cream frosting and covered in a medley of chocolate sprinkles.
For the Cake:
  • 2 1/4 cups 285 grams all-purpose flour
  • 2 1/3 cups 470 grams superfine sugar
  • 3/4 cup 90 grams dark Dutch-process cocoa powder (I use Cacao Barry Extra Brute)
  • 2 1/2 teaspoons 12 grams baking soda
  • 2 teaspoons 10 grams baking powder
  • 1 teaspoon 8 grams salt
  • 1 1/4 cups 300 ml buttermilk
  • 3/4 cup 180 ml brewed coffee or espresso
  • 2/3 cup 160 ml vegetable oil
  • 3 eggs room temperature
  • 1 tablespoon 15 ml pure vanilla extract
For the Frosting:
  • 4 1/2 cups 565 grams confectioners' sugar
  • 1 1/2 cups 340 grams unsalted butter, room temperature
  • 1 cup 280 grams Nutella (or other hazelnut spread)
  • 3/4 cup 180 ml full-fat sour cream
  • 11 ounces 330 grams best-quality dark chocolate, melted and cooled slightly
  • 1 tablespoon 15 ml pure vanilla extract
  • Pinch of salt
For the Cake:
  1. Preheat oven to 350° F. Prepare three 7-inch round cake pans with nonstick spray and parchment rounds.
  2. In bowl of electric mixer fitted with the whisk attachment, sift all dry ingredients, including sugar. Combine eggs, buttermilk, coffee, oil and vanilla in a measuring cup and beat lightly with a fork.
  3. Add milk mixture to the dry ingredients mix for 1 minute on medium speed (you may need the plastic splash-guard that comes with mixer). Divide batter evenly among prepared pans--each pan should contain about 600 grams of batter.
  4. Bake the first 2 layers for 20 minutes and rotate pans in oven. Continue to bake until toothpick or skewer comes almost clean (a few crumbs), about 5 more minutes. Cool on wire racks for 20 minutes. Repeat with remaining layer, and then gently invert onto racks until completely cool.
For the Chocolate Frosting:
  1. Put all of the ingredients in a food processor, and pulse until smooth and glossy, about 1 minute. The frosting will be very soft. Refrigerate the frosting until it thickens slightly, about 15 minutes.
Assembly of the Best-Ever Chocolate & Nutella Layer Cake:
  1. Put a dollop of frosting on a 7-inch round cake board (or cake plate) or 8-inch scalloped cake board.
  2. Put your first layer top-up on the cake board or plate, and spread about 1 cup of frosting evenly across layer. Put the second cake layer on top and repeat with another layer of frosting. Put the final cake layer top-down. Cover the cake with plastic wrap and wiggle the layers into place. Refrigerate the cake for about 30 minutes.
  3. Using a turntable, if possible, frost entire outside of cake with a thin layer of frosting to seal in the crumbs. Chill until the frosting begins to firm-up, about 15 minutes. Repeat with another thin layer of frosting, this time working to achieve a smooth finish. Chill for another 15 minutes.
  4. Apply a third coat of frosting to the cake. Holding a tall pastry comb in your dominant hand, press it gently against the side of the cake and keep it steady. Use the other hand to slowly rotate the turntable until you have gone all the way around the cake. Gently press some chocolate sprinkles around the bottom edge of the cake.
  5. Fit a medium pastry bag with a medium-large closed star tip, such as 1M, and fill about 2/3 full with frosting. Pipe a border around the top of the cake. Chill the cake until the frosting border firms up, at least 30 minutes.
  6. Cover the top of the cake (but not the piped border) with chocolate sprinkles. Once frosting softens again, the sprinkles will adhere to top. The cake will keep refrigerated for up to 3 days.