Chocolate Tower Truffle Cake™ Recipe

1. Prep and preheat

Preheat the oven to 350°F (175°C). Grease three 8-inch round cake pans, line bottoms with parchment, and grease the parchment. Lightly flour the pans or dust with cocoa powder.

2. Whisk dry ingredients together in a large bowl: flour, sugar, cocoa powder, baking powder, baking soda, and salt until evenly combined.

3. In a separate bowl, whisk together the buttermilk, vegetable oil, eggs, vanilla extract and sour cream until smooth.

4. Slowly add the wet mixture to the dry ingredients and stir until just combined. Do not overmix.

5. Stir in the hot brewed coffee gradually until the batter is smooth and thin — the hot liquid blooms the cocoa and makes a very fudgy batter.

6. Divide batter evenly among the three prepared pans (use a kitchen scale if possible, about the same volume each). Smooth tops.

7. Bake for 22–28 minutes, rotating pans halfway through, until a toothpick inserted near the center comes out with a few moist crumbs but not wet batter. Baking time will vary by oven.

8. Cool cakes in the pans for 10 minutes, then turn out onto wire racks, peel off parchment, and cool completely (at least 1 hour) before leveling and assembling. If the tops domed, level them with a serrated knife to create flat layers.

9. Combine 1/2 cup sugar and 1/2 cup water in a small saucepan. Bring to a simmer over medium heat, stirring until sugar dissolves. Remove from heat, let cool to warm, then stir in the dark rum or coffee liqueur (2 tbs). Let cool to room temperature. Use to brush and moisten cake layers before filling.

10. Place the chopped bittersweet chocolate (3 cups) in a heatproof bowl.

11. Heat 1.25 cups heavy cream in a small saucepan over medium heat until it just begins to simmer—bubbles form around the edge. Do not boil.

12. Pour the hot cream over the chopped chocolate. Let sit undisturbed for 1–2 minutes to melt the chocolate, then whisk gently from the center outward until the ganache is smooth.

13. Whisk in the room-temperature butter (1/4 cup), vanilla (1 tsp) and sea salt (1/4 tsp) until fully incorporated and glossy.

14. Cover the ganache and refrigerate until it is chilled and spreadable but not rock-hard, about 45–60 minutes. When chilled, whip the ganache with a mixer for 1–2 minutes until lightened and spreadable — this becomes your truffle cream. If ganache is too soft, chill briefly more; if too firm, let sit at room temperature a few minutes before whipping.

15. Put the chopped semisweet chocolate (1.5 cups) in a medium heatproof bowl.

16. Heat 1/2 cup of the heavy cream (from the 1.75 cups) in a small saucepan until it just simmers. Pour the hot cream over the chocolate, let sit 1–2 minutes, then whisk until smooth; this is the chocolate base. Let it cool to warm (about body temperature).

17. Whip the remaining 1.25 cups heavy cream to soft peaks. Refrigerate until needed.

18. In a clean bowl, whip the 3 pasteurized egg whites with 3 tbs sugar and a pinch of salt until glossy medium peaks form (stiff enough to hold shape but not dry).

19. Fold one-third of the whipped cream into the cooled chocolate to lighten it, then fold in the rest of the whipped cream gently to keep air. Finally fold in the whipped egg whites in two additions, using a spatula and cutting-and-folding motions until homogeneous, keeping as much volume as possible. Chill the completed mousse until slightly set but still pipeable, about 30–45 minutes.

20. Place the chopped bittersweet chocolate (1.5 cups) in a heatproof bowl.

21. Heat 3/4 cup heavy cream with 2 tbs light corn syrup just to a simmer. Pour over the chocolate, let sit 1 minute, then whisk until smooth and glossy.

22. Let the glaze cool to about 95–100°F (35–38°C) — warm but not hot — before pouring over the chilled assembled cake so it spreads smoothly and gives a glossy finish.

23. Level the three cooled cake layers so they are flat and even. Place the first layer on a cake board or serving plate and secure with a dab of truffle cream.

24. Brush the top of the first layer evenly with simple syrup (about 2–3 tbs) to moisten but not soak the cake.

25. Spread about one-third of the whipped truffle cream (ganache) in an even layer over the first cake, about 1/3–1/2 inch thick.

26. Place the second cake layer on top, press gently to level. Brush with simple syrup.

27. Pipe or spread about two-thirds of the chocolate mousse over the second layer to create a generous mousse layer (aim for 3/4–1 inch thickness). Smooth the mousse with an offset spatula.

28. Top with the third cake layer, brush with simple syrup. Use the remaining truffle cream to make a thin top layer or to seal the top (reserve a little truffle cream for decoration).

29. Apply a thin crumb coat all around the cake using any remaining truffle cream or a thin ganache layer. Smooth the coat and refrigerate the cake for 30–45 minutes to firm up.

30. After the crumb coat is chilled and firm, pour the cooled chocolate glaze over the center of the cake, allowing it to run naturally down the sides. Use an offset spatula to smooth the top to the edges if needed. Work quickly while glaze is at pouring temperature.

31. Chill the glazed cake in the refrigerator for at least 1 hour to fully set the glaze and fillings.

32. Finish by piping any reserved truffle cream around the top edge, sprinkling dark chocolate shavings, dusting with cocoa powder, and adorning with fresh berries or gold leaf as desired.

33. Let the cake sit at room temperature 15–20 minutes before slicing for cleaner cuts. Use a hot knife (dip in hot water, wipe dry) and slice with a steady, single motion. Serve chilled or slightly cool to maintain mousse texture.