I know, I know. But I do like them. :)
1/4 cup butter
1 10-ounce package miniature marshmallows (or 40 regular marshmallows)
1/4 cup peanut butter (optional)
6 cups Rice Krispies
Melt butter in large deep pan over medium-low heat. Add marshmallows and stir until completely melted. Blend in peanut butter, if using. Remove pan from heat, add Rice Krisipies, and stir until they are well-coated. Using buttered spatula, press mixture into buttered 13 x 9 x 2-inch pan. Cut when cool.