Lightly grease one 13 x 9 inch pan.
To Make Base: Combine 1-cup milk chocolate chips, 1/4 cup butterscotch chips and 1/4-cup creamy peanut butter in a small saucepan.
Cook, stirring constantly, over low heat until melted and smooth.
Spread into the bottom of the prepared pan.
Refrigerate until set.
To Make Filling: In a heavy saucepan melt the butter over medium-high heat.
Stir in sugar and evaporated milk.
Bring mixture to a boil and stir for 5 minutes.
Remove from heat and stir in the marshmallow cream, 1/4 cup of the peanut butter, and the vanilla.
Add the peanuts, and spread over the base layer.
Refrigerate until set.
To Make Caramel Layer: Combine the caramels and cream in a saucepan; stir over low heat until melted and smooth.
Spread over the top of the filling and refrigerate until smooth.
To Make Frosting Layer: In another saucepan combine 1-cup milk chocolate chips, 1/4 butterscotch chips and 1/4-cup peanut butter; stir over low heat until melted and smooth.
Pour over the caramel layer.
Refrigerate for at least 1 hour.
Cut into 1-inch squares.
Store in the refrigerator.