Preparation Steps

• Preheat oven to 350°F (176°C). Prepare three 8-inch cake pans by greasing and lining with parchment paper.
• In a large bowl, cream together butter and sugar until light and fluffy, about 3-4 minutes.
• Add sour cream and vanilla and peppermint extracts; mix until well combined.
• Add egg whites in two additions, mixing well after each; scrape bowl as needed.
• In a separate bowl, combine flour, baking powder, and salt. In a small cup, mix milk and water.
• Alternately add dry ingredients and milk mixture to batter, beginning and ending with dry ingredients, mixing well after each addition.
• Divide batter evenly among pans; bake 21-23 minutes or until toothpick inserted comes out with a few crumbs.
• Cool cakes 2-3 minutes in pans; remove to wire racks to cool completely.
• For frosting, beat butter and shortening until smooth. Gradually add half powdered sugar, mixing well between additions.
• Add water, vanilla extract, and peppermint extract; mix until smooth. Add remaining powdered sugar gradually and mix well.
• Add more water if needed for smooth consistency; fold in peppermint pieces.
• Trim cake domes flat. Place first layer on serving plate; spread 1 cup frosting evenly on top.
• Add second cake layer and spread another cup of frosting. Top with last layer and frost entire cake.
• For ganache, microwave heavy cream until boiling. Pour over white chocolate chips and let sit 2-3 minutes.
• Whisk ganache until smooth, microwaving briefly if necessary. Add red gel food coloring to desired shade.
• Let ganache thicken slightly. Use a squeeze bottle or spoon to drizzle ganache around edge of cake, leaving center open.
• Pipe ring of frosting around cake edge and decorate with candy canes, Hershey kisses, peppermints, chocolate balls, and peppermint M&Ms.
• Refrigerate cake until serving. Serve at room temperature for best flavor. Add candy decorations just before serving to prevent softening.