Heat oven to 350°F (325°F for dark or nonstick pan).
Generously grease 12-cup fluted tube cake pan with shortening; generously sprinkle with flour.
Make cake batter as directed on box, using water, oil and egg whites.
Pour about 2 cups batter into pan.
Pour about ¾ 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 and cool as directed on box.
In small bowl, mix glaze ingredients.
If necessary, stir in additional milk, 1 teaspoon at a time, until smooth and spreadable.
Spread over cake.
Sprinkle crushed candy on top.
Store loosely covered.