-chips Line an 8 inch (or you can use a 9x13 inch) pan with wax paper. Melt peanut butter chips, 6 oz condensed milk and 2 Tbsp butter, stirring occasionally. Remove from heat. Stir in peanuts. Spread in pan. In another saucepan, melt chocolate chips, 4 oz condensed milk, and 2 Tbsp butter. Spread on top of peanut butter mixture. Chill 2 hours, until firm. Turn onto cutting board. Peel off paper and cut int squares. Store tightly covered.