This brownie is Christmas in every bite! Homemade brownie, layered with peppermint bark, more brownie, then baked and topped with a white chocolate pink peppermint frosting!
Preheat oven to 350 degrees and place rack in center of oven. Line a 9x13 pan with a piece of parchment paper or foil. Spray parchment or foil with cooking spray. Set aside. Unwrap peppermint bark pieces and set aside.
Using a double boiler, or very low heat on stovetop, or a microwave, melt 12 tablespoons unsalted butter and unsweetened chocolate together. Whisk until smooth. Remove from heat and let cool.
Beat the eggs in a medium bowl. Add sugar and vanilla and mix until all ingredients are combined. Pour the cooled chocolate mixture into the egg mixture. Mix again until all ingredients are combined.
Pour the flour, baking soda and salt into the bowl with the other ingredients and fold together, just until wet and dry ingredients are combined.
Spread 3/4 of the brownie batter into the prepared pan. Place the peppermint bark pieces over the brownie layer. Top with remaining 1/4 brownie batter and smooth over peppermint pieces. Bake for 30-35 minutes. Cook just until brownies are done, and a toothpick inserted in center of pan comes out with a few moist crumbs attached.
Remove from oven. Use a spatula and gently press the edges of the brownies down while still warm if the edges rise. Do not press the center of brownies down. Let cool completely. While brownies are cooling, prepare frosting.
Melt the white chocolate in a bowl in microwave or on stovetop over low heat. Stir until smooth. Remove from heat, set aside while making frosting.
Beat the softened butter for one minute in a stand mixer or a large bowl. Add the powdered sugar, a cup at a time, and salt, and beat again for 2-4 minutes, scraping down sides of bowl 2-3 times. Add the extract, coloring and 2 tablespoons milk or cream to thin the frosting. Beat for another minute.
With the mixer in motion, add the melted white chocolate in a slow steady stream to the frosting. Add another tablespoon of milk to thin if needed.
Spread frosting on cooled brownies and immediately top with sprinkles. Place in refrigerator until the frosting is set. Remove brownies from the pan by lifting the parchment paper onto a surface for cutting. Cut into squares and serve immediately or cover tightly and store in refrigerator.