Line an 8x8 pan with parchment paper, set aside.
In a microwave safe bowl, combine the butter, cocoa, brown sugar and milk. Microwave for about 2 to 3 minutes, until the mixture is boiling.
½ cup butter, ⅓ cup cocoa, ¼ cup brown sugar, ¼ cup milk
Add powdered sugar and vanilla and stir to incorporate. Spread into the lined pan.
3 ½ cups powdered sugar, 1 teaspoon vanilla extract
Place the caramels and water in another microwave-safe bowl. Microwave until the caramels have melted, about 90 seconds. Stir until smooth, then stir in the peanuts. Spread in the pan over the chocolate layer.
11 ounces caramels, about 30 plus, 1 tablespoon water, 2 cups peanuts
In another bowl, microwave both flavors of chocolate chips to melt, about 30 to 60 seconds. Stir together, then spread over the caramel-peanut layer.
½ cup chocolate chips, ½ cup chocolate chips
Place the pan in the refrigerator to chill until firm, about an hour. Cut into 1-inch squares to serve.