Preheat your oven to 350°F (175°C) and grease three 8-inch round cake pans with butter or oil. Line bottoms with parchment paper.

In a large mixing bowl, whisk together the all-purpose flour, unsweetened cocoa powder, granulated sugar, baking soda, baking powder, and salt until combined.

In a separate bowl, whisk the eggs lightly, then add buttermilk, vegetable oil, and vanilla extract until well incorporated.

Pour the wet ingredient mixture into the dry ingredients and mix gently until just combined. Gradually stir in hot coffee until the batter is smooth.

Divide the batter among the three prepared cake pans and bake for 28-32 minutes, or until a toothpick comes out clean.

Allow the cakes to cool in the pans for 15 minutes before transferring to a wire rack to cool completely.

Beat softened butter until fluffy; gradually add powdered sugar, mixing well. Add peppermint extract and heavy cream, beating until smooth.

Once completely cool, assemble the cake by placing one layer on a plate, spreading peppermint buttercream on top, then adding the second layer.

Chill the assembled layers in the fridge for 15 minutes to set the frosting.

To prepare the ganache, heat heavy cream until simmering and pour over dark chocolate chips. Whisk until smooth and let cool slightly.

Pour the ganache over the frosted cake, allowing it to drip down the sides. Finish with crushed candy canes on top.