In large saucepan melt margarine over low heat. Add marshmallows and stir until completely melted. Remove from heat.
Add KELLOGG'S RICE KRISPIES cereal. Stir until well coated.
Using buttered spatula or wax paper, press mixture evenly into 13 x 9 x 2-inch pan coated with cooking spray. Cool. Cut into 2-inch squares. Best if served the same day.
