Preheat your oven to 350°F (175°C). In a mixing bowl, beat together unsalted butter and both granulated and brown sugars until fluffy. Then, add eggs and vanilla extract, mixing until well combined.

Gradually alternate adding your dry ingredients and buttermilk until the batter is smooth. Pour into prepared cake pans and bake for 22-25 minutes, or until a toothpick comes out clean. Allow the cakes to cool completely in the pans.

Line a 9-inch tall pan with parchment or acetate. Melt white chocolate chips with heavy cream over low heat. Once melted, let it cool for about 10 minutes.

Meanwhile, dissolve powdered gelatin in cold water. Combine with the chocolate mixture and add peppermint extract.

In a separate bowl, whip heavy cream to soft peaks. Gently fold the whipped cream into the cooled chocolate mixture. Add Andes peppermint crunch baking bits, mixing delicately.

Place one layer of the cooled chocolate cake at the bottom of the lined pan. Pour half of the candy cane mousse over the layer. Refrigerate for about 15 minutes.

Add the second chocolate cake layer on top, then pour the remaining mousse over it. Cover and refrigerate the cake for at least 5-6 hours.

For the ganache, heat heavy cream until boiling, then mix with chopped semi-sweet chocolate until smooth. Pour over the cake and add crushed peppermint candies for decoration.