Spray a 9x9 (or 9x13) pan with cooking spray. Next, line with parchment paper, leaving overhang on both sides so you can easily lift the fudge out when it’s done.

In a medium pot, mix sugar, butter and milk.

Bring the mixture to a full rolling boil using medium-high heat, stirring continuously to prevent scorching. 

Boil for exactly five minutes. This is important! Set a timer!

Remove the mixture from the heat. Working quickly, stir in chocolate chips until smooth.

Add the marshmallow creme and vanilla.

Optionally, add nuts.

Pour into the prepared pan; allow to cool completely before cutting into squares.