Line an 8x8 baking pan with foil. Spray foil with nonstick cooking spray and set aside.
In a large saucepan, add milk and sugar. Heat on medium low heat, stirring frequently and bring sugar to a boil for 2 minutes. It will be bubbly and frothy.
Stir in pumpkin and spices and heat on medium low heat, stirring frequently until smooth. Continue to boil for 18 minutes, stirring frequently and watching the mixture doesn't boil over. Remove from heat and let set for 3 minutes.
Stir in butter until melted. Add chocolate chips and let set for five minutes, and then stir until smooth. Stir in marshmallow cream until smooth and pour into prepared pan.
Refrigerate for 4-6 hours or overnight. Remove from pan by lifting out the foil and peeling away the sides. Use a knife, wiped clean after each cut, to cut fudge into 25 squares.