In a mixing bowl, combine heavy cream, milk, sugar, and vanilla extract. Stir until the sugar is dissolved.

Pour the ice cream base into a small resealable plastic bag and seal tightly, removing as much air as possible.

In a large resealable plastic bag, add the ice and salt. Place the small bag with the ice cream base inside the large bag and seal the large bag tightly.

Shake the bags vigorously for about 5-10 minutes until the ice cream base hardens.

Carefully remove the small bag from the large bag, wipe off any salt, and open the small bag to serve.