Preheat oven to 400°.
Spread marshmallows in a single layer on a jelly-roll pan coated with cooking spray. Lightly coat marshmallows with cooking spray. Bake at 400° for 3 minutes or until golden brown.
Spoon ice cream into a large freezer-safe container. Add marshmallows, graham crackers, and fudge topping. Gently stir until well blended. Cover and freeze until firm.