Ingredients
Scale
For the Chocolate Cake
- 2 ¼ cups (270 g) all-purpose flour
- ¾ cup (64 g) unsweetened cocoa powder
- 1 ¾ cups (350 g) granulated sugar
- 2 teaspoons baking powder
- 1 ½ teaspoons baking soda
- ½ teaspoon fine salt
- 3 large eggs, room temperature
- 1 cup (240 ml) whole milk, room temperature
- ½ cup (120 ml) neutral vegetable oil
- 2 teaspoons vanilla extract
- 1 cup (240 ml) hot brewed coffee or hot water
For the Chocolate Buttercream
- 1 ½ cups (340 g) unsalted butter, softened
- 5 cups (600 g) powdered sugar
- ¾ cup (64 g) unsweetened cocoa powder
- 2 teaspoons vanilla extract
- ¼ teaspoon fine salt
- 5–6 tablespoons (75–90 ml) heavy cream
For the Chocolate Ganache
- 8 oz (225 g) semisweet chocolate, finely chopped
- ¾ cup (180 ml) heavy cream
For the Crunch Filling
- 1 cup crushed chocolate sandwich cookies
- ¾ cup roughly chopped chocolate wafer pieces
- ½ cup chocolate-covered crispy bites
For the Chocolate Crown
- Chocolate wafer bars
- Vanilla wafer bars
- Striped chocolate wafer rolls
- Chocolate sandwich cookies
- Chocolate-covered malt-style balls
- Chocolate-covered crispy bites
- Assorted chocolate pieces
- Extra crushed cookies and wafer crumbs
For the decorative ingredients, I recommend listing them “as needed” rather than inventing fixed weights. The exact amount depends on the size of the wafers and chocolates used.
Instructions
- Prepare the pans. Preheat the oven to 350°F (175°C). Grease three 8-inch round cake pans. Line the bottoms with parchment circles and lightly grease the parchment.
- Combine the dry ingredients. In a large mixing bowl, whisk the flour, cocoa powder, sugar, baking powder, baking soda, and salt until evenly combined and free of large cocoa lumps.
- Add the wet ingredients. Add the eggs, whole milk, vegetable oil, and vanilla. Mix on low speed until mostly combined.
- Add the hot liquid. Slowly pour in the hot coffee or hot water while mixing on low. The finished batter will be thin. This is expected.
- Divide the batter. Divide evenly between the three prepared pans. For the most even layers, weigh the filled pans or batter portions.
- Bake. Bake for approximately 25–30 minutes. Begin checking around 25 minutes. A toothpick inserted near the center should come out clean or with a few moist crumbs, but no wet batter.
- Cool completely. Leave the cakes in their pans for about 10 minutes. Turn them onto wire racks, remove the parchment, and allow them to cool completely before frosting.
- Prepare the buttercream. Beat the softened butter for about 3 minutes until creamy. Gradually beat in the powdered sugar and cocoa powder. Add vanilla and salt. Add heavy cream one tablespoon at a time until the frosting is smooth, fluffy, and firm enough to hold a layer cake.
- Prepare the crunch. Combine the crushed sandwich cookies, chopped chocolate wafers, and crispy chocolate bites shortly before assembling. Keep some larger pieces for texture rather than reducing everything to fine crumbs.
- Fill the first layer. Place one completely cooled cake layer on a cake board or serving plate. Spread about ¾ cup chocolate buttercream evenly across the surface.
- Add crunch. Scatter a light layer of the cookie-wafer mixture over the buttercream. Leave roughly ½ inch around the edge clear so loose pieces do not interfere with the cake’s stability.
- Repeat. Add the second cake layer and repeat with buttercream and crunch. Place the third cake layer on top. Position it bottom-side up for a flatter surface.
- Crumb coat. Spread a thin layer of buttercream over the entire cake to trap crumbs. Refrigerate for 20–30 minutes, or until firm.
- Final coat. Cover the chilled cake with the remaining chocolate buttercream. Smooth the top and sides. Return it to the refrigerator while preparing the ganache.
- Prepare the ganache. Put the finely chopped semisweet chocolate in a heatproof bowl. Heat the cream until steaming and just beginning to simmer around the edges. Pour it over the chocolate and leave undisturbed for 2–3 minutes. Stir gently until completely smooth.
- Cool the ganache. Allow it to cool until slightly thickened but still pourable. Do not pour very hot ganache onto buttercream.
- Test the drip. Make one test drip down the chilled cake. It should travel slowly and stop before reaching the bottom. If it runs too quickly, allow the ganache to cool longer.
- Decorate with ganache. Create drips around the perimeter, then spread the remaining ganache across the top.
- Build the chocolate tower. Position the tallest wafer rolls and bars near the center and back. Add cookies and medium pieces around them. Fill gaps with chocolate-covered balls, crispy bites, and broken chocolate pieces.
- Finish. Scatter cookie and wafer crumbs across the ganache. Add the most delicate wafer decorations as close to serving time as possible for maximum crunch.
Notes
- Do not frost warm cake. The layers must be completely cool.
- Room-temperature eggs and milk combine more readily with the other ingredients.
- Hot coffee deepens the chocolate character, but hot water works if you prefer not to use coffee.
- The batter is supposed to be thin after adding the hot liquid.
- Do not overload the filling with loose cookie pieces. Too much crunch can cause the layers to slide.
- Keep about ½ inch around the perimeter of each filling layer clear.
- Chill after the crumb coat. This makes the tall cake considerably easier to finish.
- Test the ganache on one section before creating all the drips.
- Add delicate wafers near serving time because moisture from frosting and ganache gradually softens them.
- For cleaner slices, remove tall decorations from the cutting area and use a sharp knife warmed in hot water and wiped dry.
- Food-safety note: never taste the uncooked cake batter. The FDA states that flour is a raw food and that both raw flour and raw eggs can contain harmful bacteria.
- Prep Time: 1 hour
- Additional/Chilling Time: 1 hour 30 minutes
- Cook Time: 30 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American-inspired