01 -
Line an 8×8 or 9×9 inch square pan with aluminum foil. You can also use a 9×13 inch pan for thinner fudge. Set aside.
02 -
In a medium saucepan over medium heat, combine the sugar, butter and evaporated milk. Stir constantly until the mixture comes to a full boil.
03 -
Maintain the boil while stirring constantly for 4-5 minutes or until the candy thermometer reaches 234ºF (112ºC).
04 -
Remove from the heat and add the chocolate chips, marshmallow creme, salt and vanilla extract. Stir until fully combined and smooth.
05 -
Stir in the chopped walnuts if using.
06 -
Carefully pour the fudge into the prepared pan. If desired, sprinkle additional walnuts on top.
07 -
Allow the fudge to fully set and cool before cutting, approximately 4-6 hours at room temperature.