To make peanut butter fudge with marshmallow fluff is very fun and easy. You will need 2 cups sugar, 1 cup milk, 1 12oz jar peanut butter smooth or crunchy, 1 jar marshmallow fluff and 1 teaspoon vanilla extract. Boil sugar and milk to a soft ball stage and remove from heat. Add peanut butter, marshmallow fluff and add the vanilla. Pour into an 8x8x8 pan. After it cools you can cut the fudge.