Directions

1. Put a rack in the middle of the oven, and preheat the oven to 350 degrees F. Butter 2 (9 by 2-inch) tephlon round cake pans. Line the bottom of each with a round of parchment or waxed paper, and then butter the paper. Sift the flour, cocoa, baking soda, and salt together onto waxed paper. Cream the butter, and sugars in a large bowl using an electric mixer at medium-high speed until light and fluffy, about 4 minutes in a standing mixer or 5 minutes with a handheld mixer. Add the room temperature eggs, 1 at a time, mixing until completely incorporated before adding additional eggs. Add the chocolate and vanilla and mix until combined. Turn the mixer to low and slowly add the dry ingredients and the buttermilk alternately in 3 batches, starting and ending with dry ingredients and mixing until combined. Divide the batter between the cake pans, spreading evenly, and bake until a wooden skewer inserted in the center of each cake layer comes out clean, 25 to 35 minutes. Allow the cake layers to cool in the pans on racks for 10 minutes. Run a thin knife around edge of each layer, then invert them onto racks. Peel off paper and cool layers completely. Frosting: In a standing mixer fitted with a whisk attachment, combine the butter, salt, and 2 cups of the confectioners' sugar until light and fluffy. Add the melted chocolate, vanilla, and remaining sugar. Whisk on medium-high until smooth and fluffy. Assemble the cake by using 1 cup frosting to frost between the layers, and then frost the top and sides with the remaining frosting. To decorate the graveyard cake: Finely crush the chocolate wafer cookies in a plastic bag with a rolling pin or use a food processor. Sprinkle the top of the cake generously with cookie crumbs. Write "RIP" and other scary words on the chocolate sandwich cookies with black icing. Cut slits in the cake to insert cookies for gravestones, and add candy rocks, pumpkins, Candy Bones, Chocolate Trees and cotton candy. Arrange Candy Bones around the base of the cake.;
2. Line a cookie sheet with aluminum foil. Stick marshmallows onto both ends of the pretzels, with the marshmallows' flat sides parallel to the pretzel. Put the chips in a heat proof bowl over barely simmering water and let melt, stirring frequently. As soon as the chips are just melted, stir in the melted butter. Take the pan off the heat, remove the bowl from the pot, and allow it to cool slightly. Dip each pretzel bone in the chocolate and lift them out with a fork, letting the excess drip back into the bowl. Lay the bones on the baking sheet and refrigerate for 30 minutes to harden the chocolate.;
3. Line a cookie sheet with aluminum foil. Spoon the melted chocolate into a small resealable food storage plastic bag and seal the bag. Cut a small hole in the bottom corner of the bag. Squeeze melted chocolate in the shape of trees onto the foil. Refrigerate the trees. Remove the trees and insert them into the cake, decorating with cotton candy as cob webs.;