Combine first 4 ingredients in a microwave-safe bowl; microwave on high for 3 minutes or until mixture boils, stirring after one minute. Stir in powdered sugar and vanilla; pour into a buttered 8x8" baking dish and set aside.
Heat caramels and water in another microwave-safe bowl on high 2 minutes or until melted, stirring after 1 minute; stir in peanuts. Spread over chocolate mixture; set aside.
Microwave chocolate chips in a microwave-safe bowl on high 1 minute, stirring until melted. Pour evenly over caramel layer. Refrigerate until firm. Cut into squares.