Double Decker Fudge
["1 c. Reese's peanut butter chips", "1 (14 oz.) can sweetened condensed milk (not evaporated)", "1 tsp. vanilla extract", "1 c. semi-sweet chocolate chips"]
["In a 2-cup glass measure with handle, combine peanut butter chips and 2/3 cup sweetened condensed milk.", "Cook on 100% power (High) in microwave for 1 to 1 1/2 minutes, stirring after 1 minute, until chips are melted and mixture is smooth.", "Stir in 1/2 teaspoon vanilla; spread evenly into foil lined 8-inch square pan."]
["butter chips", "condensed milk", "vanilla extract", "semi-sweet chocolate chips"]