01 -
Preheat oven to 350°F. Grease and flour three 6-inch cake pans, line bottoms with parchment paper.
02 -
Whisk together flour, graham cracker crumbs, baking powder, baking soda, and salt in a medium bowl.
03 -
Beat butter until smooth, then add sugars and beat until fluffy (2-3 minutes). Add eggs one at a time, then vanilla. Alternate adding flour mixture and buttermilk, starting and ending with flour.
04 -
Divide batter between pans, smooth tops, and tap pans on counter. Bake for about 40 minutes until toothpick comes out clean. Cool 10 minutes in pans, then turn out onto wire racks.
05 -
Pour hot cream over chopped chocolate, let stand 2 minutes, then stir until smooth. Chill until thickened but still soft. Whip until fluffy and lightened in color.
06 -
Layer cakes with whipped ganache between layers. Chill to set. Cover entire cake with marshmallow fluff and toast with a kitchen torch.