Whisk milk, vanilla extract, and salt together in a large bowl.
Whip cream in a separate large bowl until peaks stay firm after the blender has turned off.
Fold 1 cup of the whipped cream mixture into the milk mixture, until combined.
Carefully fold the remaining whipped cream into the milk mixture until it is well blended.
Pour into a 6-cup freezer-safe container. Wrap with plastic wrap and freeze for 2 hours.
Drop fudge in dollops over the top of the ice cream, then sprinkle the peanuts over the ice cream as well. Gently swirl the ice cream using a spatula. Do not mix too much, it should just be a light swirl.
Place back in the freezer for an additional 6 hours. Keep frozen until ready to serve.