Preheat oven 350°. Spray 9- x 9-inch baking pan with nonstick cooking spray; set aside.
Melt caramels in 1/2 cup evaporated milk in medium saucepan over low heat, stirring constantly, about 12 minutes; set aside.
Microwave Skippy® Creamy Peanut Butter with Country Crock® Spread in medium microwave-safe bowl 1 minute or until melted; stir until smooth. Stir in remaining 1/3 cup evaporated milk and cake mix until smooth, about 1 minute.
Press 1/2 of the cake mixture into prepared pan. Bake 10 minutes. Remove pan from oven, then spoon on melted caramel mixture. Break off soft remaining cake mixture and sprinkle over caramel layer. Bake an additional 18 to 20 minutes or until top is set. Cool on wire rack until room temperature. Cut into 18 bars and serve, if desired, with Breyers® Natural Vanilla Ice Cream. Store tightly covered at room temperature.
