Several recipes, including one published by Kellogg’s, add peanut butter to traditional Rice Krispies treats. Recipes differ on whether to use melted marshmallows or corn syrup.
To make Kellogg’s peanut butter treats, melt 3 tablespoons of butter in a large saucepan over medium heat. Kellogg’s advises against using tub margarine. Add a 10-ounce package of marshmallows, and stir until melted. Remove the saucepan from the heat, and stir in 1/2 cup of peanut butter. Pour in 6 cups of Rice Krispies while stirring to coat completely. Firmly press the mixture into a greased 13-by-9-inch pan. Let the mixture cool and then cut into 2-inch squares.