In a tall jar, combine 1.5 cups of chocolate milk, one package of sugar-free pudding mix, 1 teaspoon of vanilla extract, and 0.5 tablespoon of granulated sugar. Whisk vigorously until smooth, about 2-3 minutes.

Pour the blended mixture into the Ninja Creami container and freeze for a full 24 hours.

After 24 hours, remove from freezer and let sit at room temperature for about 10 minutes.

Insert the softened container into the Ninja Creami base and lock into place.

Select the 'lite ice cream' setting and process for 2-5 minutes.

Once processing is complete, add 1 teaspoon of chocolate milk and press the re-spin button.

Scoop the frosty into glasses and serve immediately.