Make the Chocolate Cake:
- Pre-heat the oven to 350-degrees F. Grease and flour three 8-inch round cake pans and set aside.
- Sift together the flour, cocoa powder, baking soda, baking powder, and salt. Set aside.
- In the bowl of an electric mixer, mix the oil and sugar on medium until combined.
- With the mixer on low, add in the vanilla and eggs, one at a time. Mix until combined and smooth. Stop the mixer and scrape down the bowl.
- With the mixer on low, add the dry ingredients and buttermilk in alternating batches, starting and ending with the dry ingredients. Carefully stream in the hot water. Mix on medium speed until smooth, but not more than 20-30 seconds after the water has been added.
- Evenly distribute the batter into the prepared pans. Bake for 25 to 28 minutes, or until a toothpick inserted into the center of the cakes comes out clean. Let cool on a wire rack from 10 minutes before removing the cakes from their pans.
Make the Graham Frosting:
- Using an electric mixer, beat the butter and cream cheese together on medium until smooth.
- With the mixer on low, gradually add in the sugar, milk, and vanilla.
- Once the sugar begins to incorporate, turn the mixer up to medium-high and mix until light and fluffy.
- Mix in the graham cracker crumbs. Adjust the sugar and cream quantities until desired consistency is achieved.
Make the Chocolate Ganache Frosting:
- Place the chocolate in a heat-safe bowl and set aside.
- In a saucepan, slowly bring the cream to a simmer. Remove from the heat and gently pour over the chocolate.
- Allow to stand for about 30 seconds, then gently whisk until smooth. Stirring intermittently, allow the ganache to cool at room temperature until it reaches a slightly thickened, yet spreadable consistency.
Make the Meringue:
- In the bowl of an electric mixer, stir together the egg whites and sugar. Fill a saucepan with a few inches of water and bring to a simmer. Place the mixer bowl on top of the saucepan to create a double-boiler. Stirring intermittently, heat the egg mixture until it reaches 160 degrees on a candy thermometer.
- Carefully return the bowl back to the stand mixer and whisk on high until glossy, stiff peaks form – about 8 to 10 minutes, or until the outside of the mixer bowl returns to room temperature.
- Add vanilla and mix to combine. Use fairly immediately.
Assemble the Cake:
- After the cakes have cooled, trim the tops until even. Place the bottom layer of cake on a cake board or serving dish. Spread on half of the graham frosting with an offset spatula. Top the with the next layer of cake and repeat.
- Once the ganache has cooled to a spreadable consistency, begin frosting the cake. If the ganache is on the runny side, work with only small amounts at a time. The ganache may be difficult to work with at first, but eventually it should come together.
- Before the ganache sets, sprinkle the sides of the cake with extra graham crumbs.
- Pipe the meringue on top of the cake using a French star tip like an Ateco 869. Lightly toast meringue with a culinary torch, if desired.