Preheat oven to 400°F. Mix flour, sugar, baking powder and salt in large bowl; set aside. Beat egg in medium bowl; stir in milk, butter and orange peel. Add to flour mixture; stir just until moistened. (Batter will be lumpy.) Stir in cereal.
Spoon batter evenly into 12 greased or paper-lined medium muffin cups, filling each cup 2/3 full.
Bake 20 min. or until golden brown. Serve warm. Makes 1 doz. muffins.