Family Tested & Approved
Place sugar, butter and milk in a microwave bowl. Cook 2 minutes on high. Remove bowl and using a hand mixer, mix until combined. Return to microwave for an additional 30 seconds.
Remove from microwave and add the peanut butter, and mix with a mixer or by hand until combined.
Spread into an foil lined 8x8 baking dish. Let cool before cutting. I always put mine in the refrigerator for several hours.