Line a 9x13 inch pan with parchment paper or nonstick foil.

In a large double boiler or in a heat-proof bowl set over simmering water, melt the chips.

Add the peanut butter and stir until smooth, then stir in the peanuts.

Remove from heat, let cool slightly, then add marshmallows.

Spread mixture in pan and refrigerate for at least two hours. Lift from pan, set on a cutting board and cut into desired size squares/bars.

The mud should be stored in the refrigerator or freezer.