01 - Preheat oven to 350°F (175°C). Grease and line a 9x13-inch baking sheet or cake pan with parchment paper.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, and salt.
03 - In a large mixing bowl, cream the softened butter and granulated sugar with an electric mixer until light and fluffy, approximately 3 minutes.
04 - Beat in the eggs one at a time, ensuring thorough mixing after each addition. Stir in the vanilla extract.
05 - Gradually add the flour mixture to the wet ingredients in three alternating additions with the whole milk, starting and ending with the flour mixture. Mix until just combined.
06 - Gently fold in 1/2 cup of crushed candy canes into the batter.
07 - Spread the batter evenly into the prepared baking pan. Bake for 28–32 minutes, or until a toothpick inserted into the center emerges clean. Allow the cake to cool completely in the pan.
08 - For the fudge drizzle, combine semisweet chocolate chips, heavy cream, and butter in a small saucepan over low heat. Stir continuously until the mixture is melted and smooth. Remove from heat and allow to cool slightly until thickened but still pourable.
09 - Drizzle the slightly cooled fudge sauce generously over the completely cooled cake. Immediately sprinkle the top with additional crushed candy canes and chopped peppermint bark or chocolate.
10 - Allow the fudge topping to set for at least 15 minutes before slicing and serving.