Start by following the instructions on your boxed brownie mix to bake the base. I usually bake mine in a 9×9-inch pan and let it cool completely. This prevents the other layers from sliding off and keeps the brownies firm yet fudgy.
Combine marshmallow fluff and peanut butter in a medium bowl until smooth. I sometimes microwave the mixture for 10-15 seconds to make spreading easier. Spread evenly over the cooled brownie base.
Melt caramel bits with milk in the microwave for 1 minute, stirring every 30 seconds. Pour over the nougat layer and spread gently. Make sure it’s even to hold the peanuts and chocolate layer.
Immediately scatter roasted peanuts over the caramel. Press them lightly so they stick without sinking. This layer adds that irresistible salty crunch with each bite.
Melt milk and dark chocolate chips with peanut butter in the microwave, stirring frequently until smooth. Pour over the peanut layer and spread evenly. Allow it to set before slicing into squares for the perfect presentation.