Prepare the Pan: Using wax or parchment paper, line the baking dish, leaving a small overhang for easy removal at a later time.
Mixing the Ingredients: Put the butter, sugar, and evaporated milk into a big pot. Stirring regularly, cook over medium heat until mixture reaches a boiling point.
Boil and Stir: After it starts to boil, keep stirring and let it cook for four to five minutes. Take off the heat.
Add the Chocolate Chips and Marshmallow crème: Using a whisk, thoroughly incorporate the chocolate chips, marshmallow crème, and vanilla extract until smooth.
Pour and Cool: Transfer the mixture into the baking dish that has been ready. Add chopped nuts to the top for texture, if you'd like.
Chill and Serve: After allowing the fudge to cool for roughly two hours at room temperature, place it in the refrigerator to chill for an additional 2 hours or until firm.