Preheat oven to 350. Prepare a 12-cup tube pan with cooking spray; set aside. In a mixing bowl, combine cake mix, water, oil, and egg whites. Mix well. Pour two cups batter into bottom of prepared pan. Pour 3/4 cup batter into a small bowl. Add red food coloring and peppermint extract. Mix until batter is red. Pour over white batter in pan. Pour remaining white over top. Bake for 45 minutes, or until toothpick inserted in center comes out clean.Cool ten minutes. Invert onto a serving platter; set aside. To prepare glaze, combine powdered sugar, milk, and vanilla extract in a 2-cup liquid measure. Mix until smooth. Pour evenly over cooled cake. Sprinkle top with crushed peppermint candy.