Combine:

1 box rice cereal (such as Chex - 17.5 oz)
1/2 c butter
2 c chocolate chips
3/4 c peanut butter
4 cups powdered sugar

Pour cereal into a paper bag.  In saucepan, melt butter and chocolate chips.  Pour over cereal in bag.  Seal and shake.    Pour in powdered sugar and shake again.

Store in an airtight container.