1Heat oven to 350°F. Spray bottom and sides of 13x9-inch pan with cooking spray (without flour).
2In medium bowl, stir cookie mix, 1/2 cup butter, the vanilla and egg until soft dough forms. Press in pan. Bake 15 minutes or until set.
3Meanwhile, in 1-quart saucepan, heat caramels, 2 tablespoons butter and the condensed milk over medium-low heat 5 to 10 minutes, stirring frequently, until caramels are melted. Remove from heat. Carefully pour filling over partially baked crust; spread evenly. Sprinkle with peanuts. Bake 15 to 18 minutes or until filling is bubbly. Cool completely in pan on cooling rack, about 1 hour. Cut into 6 rows by 4 rows.