Place cashews in bowl and cover with 2 inches of water. Soak 3 hours or overnight. Drain cashews.
Add all ingredients, including soaked cashews, to a high-powered blender. Blend on high for 1 minute or until sauce is completely smooth. Taste for flavor and add more sea salt, cider vinegar, or 1/2 tsp garlic powder.
Either use immediately or store in an air-tight container in the refrigerator. The sauce stays fresh for up to 10 days. Note: Sauce will thicken in the refrigerator, so stir well before using.