Combine peanut butter morsels, corn syrup, and 2 tablespoons butter in top of a double boiler; bring water to a boil.
Cook over hot water until morsels melt; stir well.
Add cereal, and stir well.
Press half the mixture into a buttered 12 x 8 x 2 inch baking dish, and chill while preparing chocolate layer.
Set remaining cereal mixture aside.
Combine chocolate morsels and 1/4 cup butter in top of a double boiler; bring water to a boil.
Cook mixture over hot water until chocolate melts; stir well.
Add powdered sugar, milk, and vanilla extract, stirring until well blended.
Spread chocolate mixture over chilled layer.
Spread remaining cereal mixture over chocolate layer; press layered mixture firmly.
Chill until set.
Cut into bars.