Make as a cake by baking in an 8-inch square pan for about 30 minutes. Add extra powdered sugar for thicker, pipeable frostin, chill before piping. Dairy-free option: use vegan butter, plant milk + vinegar instead of buttermilk, and dairy-free cream cheese. Decorate with crushed gingerbread cookies, cinnamon sugar, or a caramel drizzle.