In the quart-size freezer bag, combine the half and half, sugar, pinch of salt, and vanilla. Press air out and seal. In the gallon-size freezer bag, combine ice and 3/4 cup salt; add the sealed quart-size freezer bag.
Seal the quart-size freezer bag. Shake and knead for 5-10 minutes or until ice cream is frozen and thickened. Serve immediately or store in freezer.
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Serving size: This recipe makes one kid-sized serving (about 1 cup).
Fun Tip: You can top your ice cream in a bag with fruit jams and jellies, chocolate syrup, caramel sauce, or other favorite ice cream toppings.