Preheat your oven to 350°F. Grease and flour two 9-inch round cake pans. In a large mixing bowl, sift together the flour, cocoa powder, baking powder, baking soda, and salt. In another bowl, cream the butter and sugar until light and fluffy. Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract.

Gradually add the dry ingredients to the wet mixture, alternating with the buttermilk. Mix until just combined. Divide the batter evenly between the prepared pans.

Bake for 25-30 minutes or until a toothpick inserted into the center comes out clean. Allow the cakes to cool in the pans for 10 minutes before transferring them to a wire rack to cool completely.

In a large bowl, beat the butter until creamy. Gradually add powdered sugar, alternating with heavy cream. Stir in vanilla extract. Add black food coloring a little at a time until the desired shade is reached. Beat until smooth and fluffy.

Once the cakes are cool, level the tops with a serrated knife. Apply a thin layer of frosting between the layers and stack them. Cover the entire cake with a crumb coat and chill for 20 minutes.

Apply a second, thicker layer of frosting. Roll out the black fondant and cover the cake, smoothing out any air bubbles. Use a brush to apply gold edible paint or luster dust to create elegant patterns. Add golden sprinkles or edible gold leaf for extra sparkle.

Serve the cake on a decorative cake stand. Pair with sparkling apple cider or a rich black tea. Add sparklers or edible gold stars for a final festive touch.

Store any leftover cake in an airtight container in the refrigerator for up to 3 days. Allow the cake to come to room temperature before serving for the best flavor and texture.