PREHEAT oven to 400°F. Combine flour, sugar, baking powder and baking soda in large bowl; set aside. Mix cereal and milk in medium bowl; let stand 5 min. Stir in egg and margarine. Add to flour mixture; stir just until moistened. (Batter will be lumpy.)
SPOON evenly into 12 greased or paper-lined medium muffin cups, filling each cup 2/3 full.
BAKE 18 to 20 min. or until golden brown. Serve warm.