Lightly grease a 9x12 baking pan.
Measure out all the ingredients before starting.
Melt the butter in a large stock pot over medium heat.
12 oz. margarine or butter
Add the sugar and evaporated milk, then stir to combine.
1 13 oz. can evaporated milk, 5 cups granulated sugar
Bring to a rolling boil for 8 minutes. When the temperature reaches 238-degrees F, remove it from the heat.
Quickly add the vanilla extract, peanut butter, marshmallow fluff, and chocolate chips.
2 teaspoons pure vanilla extract, 2 tablespoons peanut butter, 2 large tablespoons marshmallow fluff, 12 oz. semi-sweet chococolate chips
Beat vigorously for 3 minutes.
Pour the fudge into the prepared pan and let set for 1 hour until completely set and cooled before cutting.