Using a blender with the ability to cook food, blend all ingredients, on high for 5 minutes, or until sauce begins to thicken. (I can hear my Vitamix motor slow down and the sound deepens as the sauce hits the thick mark.)
Once thickening has begun, stop the blender and quickly transfer to a large container that holds at least 6 cups. The cheese sauce will continue to thicken as it cools even slightly.