Ingredients
Equipment
Method
Bake the chocolate cake
- Preheat the oven to 350°F, then grease two 9-inch round pans. Keep them ready for a smooth batter bake.
- Whisk together the all-purpose flour, granulated sugar, unsweetened cocoa powder, baking soda, baking powder, and salt in a bowl. Mix until the dry ingredients look evenly combined.
- Whisk together the eggs, buttermilk, strong brewed coffee, cooled, vegetable oil, and vanilla extract in a separate bowl. Blend until the liquid mixture is uniform.
- Combine the wet ingredients with the dry ingredients and mix until smooth. Stop when no dry streaks remain to avoid overmixing.
- Divide the batter between the pans and bake for 30-35 minutes at 350°F. Look for the centers to spring back and a toothpick to come out mostly clean.
- Cool the cakes completely before assembling. This cooling step prevents the ganache and meringue from melting.
Make the chocolate ganache
- Heat the heavy cream until it reaches a simmering point, then pour it over the chopped dark chocolate. Let it sit undisturbed for 2 minutes so the chocolate softens.
- Stir the mixture until smooth after the 2-minute rest. Continue until you see a glossy ganache with no visible chocolate bits.
- Cool the ganache until pourable but still fluid. It should coat a spoon and fall slowly, not thicken into fudge.
Make the marshmallow meringue
- Combine the egg whites, granulated sugar, and cream of tartar in a double boiler. Whisk over simmering water until the sugar dissolves and the mixture is hot.
- Transfer to a mixer and beat until stiff glossy peaks form. Stop when the meringue holds sharp ridges that look shiny.
Assemble and finish
- Fill the cake with ganache and meringue between the layers. Spread evenly so each slice shows both chocolate and marshmallow.
- Frost the outside with the marshmallow meringue. Use smooth strokes to create a thick, mounded surface for toasting.
- Press the graham cracker crumbs around the base of the cake. Cover the bottom edge so the crumble is visible at the base.
- Use a kitchen torch to toast the meringue to golden in dramatic patches. Watch for quick color changes to amber-gold without burning.
- Drizzle the remaining ganache over the top. Let it run down the sides to create a drip effect.
Notes
For clean ganache drips, cool the layers until completely room temperature, then assemble promptly—warm cake will loosen the frosting. Store the finished cake covered in the refrigerator for up to 3 days; keep it tightly covered because the meringue can weep over time. Freezing is not recommended for the torched meringue. For a lighter option, use low-fat buttermilk in the cake (texture stays tender, but the flavor is slightly less rich).