Elvis S’mores Cake

Instructions

1. To make the cake: Preheat the oven to 350 degrees F. Grease two 9” round cake pans with baking spray, line them with parchment paper, and grease parchment.
2. In a medium bowl, whisk together the flour, graham cracker crumbs, baking powder, baking soda, salt, and cinnamon. Set aside.
3. In a large mixing bowl, cream the butter and sugars together until light and fluffy. Add the eggs, one at a time, scraping down the sides of the bowl as needed.
4. Add a third of the dry ingredients, then half of the buttermilk, mixing after each addition until just combined. Scrape down the bowl and continue alternating the dry and wet ingredients.
5. Divide the batter between the prepared cake pans, smoothing tops. Bake until a toothpick inserted into the center comes out clean, about 30-35 minutes.
6. Cool in pan on a rack for 20 minutes, then run a knife between the cake edges and pan before inverting each layer on a rack. Discard the parchment paper and flip the cakes back upright on the rack.
7. Let cool completely. (a process you could speed up by placing cakes in the fridge).
8. To make the filling: Place the chocolate in a heatproof bowl. Combine the heavy cream and salt in a small saucepan, and bring to a simmer. Pour over the chocolate and let sit for 1 minute, then whisk until smooth. Set bowl over another bowl filled with ice water and stir until it firms up to a spreadable consistency.
9. Make the frosting: Place egg whites, granulated sugar, and cream of tartar in a heatproof bowl of an electric mixer. Set over a saucepan with simmering water. Whisk constantly until sugar is dissolved and whites are warm to the touch, about 3 minutes.
10. Transfer the bowl to an electric mixer fitted with the whisk attachment, and beat, starting low and gradually increasing to high, until stiff glossy peaks form 4 to 7 minutes. Add vanilla and mix until combined. Use immediately.
11. Assembly: Use a long serrated knife to level the top of the cakes; gently taking off the domed part. Place one cake layer face up and spread peanut butter ganache thickly over the bottom layer. Scatter the banana slices over the ganache. Place top layer over the bottom. Chill the cake for 10-15 minutes to firm up the filling so the top cake doesn't slide when decorating.
12. Frost the cake by spreading a thin layer over the top and sides, covering for crumbs. Transfer to fridge for 5 to 10 minutes, and let sit. Then generously coat top and sides with additional frosting. Put the remaining frosting in a piping bag fitted with a large round piping tip. Create big marshmallow dollops decoratively over the top of the cake. Dipping your finger in water between each dollop to push down the top of each where you pulled the piping bag away. With a kitchen torch on low, lightly brown the dollops, creating the toasted marshmallow effect.