Put the cashews in a medium bowl and pour over enough water to cover the cashews by 1 inch. Soak for at least 2 hours or as long as overnight. Drain and rinse well.

In a food processor, combine the cashews, ¼ teaspoon of the salt, and ¼ cup cold water and process until smooth, about 2 minutes. Using a rubber spatula, scrape down the sides. Add another ¼ cup water and process until creamy and smooth, 3 to 4 minutes more. If you prefer a thinner consistency, adjust the water accordingly. Taste and add the remaining salt as needed. 

Use immediately or store in an airtight container in the refrigerator for up to 4 days.