Makes about 2 dozen bars
Generously butter a 13x9-inch glass dish.
In a large 3-quart saucepan melt the butter over low heat. Stir in the peanut butter. Once peanut butter has melted, add your marshmallows. Stir frequently until marshmallows are melted and mixture is smooth.
Remove the marshmallow mixture from the heat, and pour your cereal in to the pan. Stir in cereal and mix gently (you don't want to crush up your cereal) until well coated.
Dump the cereal mixture into your greased glass dish and carefully press down and spread out the mixture, be careful, as the cereal will be quite warm. Sprinkle any toppings on, and press a little into the cheerios, chocolates will melt a little, if using candy coated, they won't melt, so make sure you press them in pretty well.
Let cool for about 30 minutes. Cut in to squares and enjoy.
These are best enjoyed within 24 hours, and are okay after 2 days, but not the best after 3 days.