Add Sugar: Carefully, remove the bowl from the microwave and add the powdered sugar, salt, and vanilla extract. Stir with a wooden spoon until combined.

Move to Baking Dish: Line 8-inch square pan with parchment or wax paper and transfer the peanut butter mixture into the pan or baking dish.

Refrigerate: Next, place the fudge mixture in the refrigerator for at least two hours, until the fudge sets. Finally, cut the fudge into 20 small squares. Enjoy!