Chocolate-Peanut Butter Mallow Bars

1 pkg Devil's food cake (two-layer size)
1/2 C butter (1 stick melted)
2/3 C cold milk (divided)
3/4 C creamy peanut butter
1 jar Jet-Puffed Marshmallow Creme
1/2 C Planters salted peanuts
6 sq Baker's semi-sweet chocolate (coarsely chopped)

Heat oven to 350 degrees. Mix dry cake mix, butter and 1/3 cup milk until blended. Press 2/3 into bottom of 13X9- inch pan. Bake 12-14 minutes or until center is almost set. Cool 3 minutes.

Mix peanut butter and remaining milk. Spread onto crust. Top with spoonfuls of marshmallow creme and remaining cake mixture. Sprinkle with nuts and chocolate. Press gently into cake mixture.

Bake 18 minutes or just until center is set. Cool before cutting into bars.