crushed candy canes or
crushed hard peppermint candy, if desired
Heat oven to 350ºF. Generously grease and flour 12-cup fluted tube (bundt cake) pan.
In large bowl, beat cake mix, water, oil and egg whites with electric mixer on low speed 30 seconds; beat on medium speed 2 minutes, scraping bowl occasionally.
Pour about 2 cups batter into pan. Pour about 3/4 cup batter into small bowl; stir in food color and peppermint extract. Carefully pour pink batter over white batter in pan. Carefully pour remaining white batter over pink batter.
Bake 45 to 50 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes. Turn pan upside down onto wire rack or heatproof serving plate; remove pan. Cool cake completely, about 1 hour.
In small bowl, mix all icing ingredients. Stir in additional milk, 1 teaspoon at a time, until smooth and spreadable. Spread icing over cake. Sprinkle top with crushed candy.