Just in case I don't have the recipe on the back of the box on hand...
3 T. margarine or butter
1 package (10oz, about 40) regular marshmallows
6 C. Rice Krispies cereal
Melt butter in large saucepan over low heat. Add marshmallows and stir until melted. Remove from heat. Add cereal. Stirl until well coated. Using a buttered spatula press mixture evenly into a 13 by 9 inch pan coated with cooking spraky. Cut into 2-inch squares when cool.
