To make vegan mac and cheese, completely cover the nuts in a bowl with water. Let soak anywhere from 2-6 hours, or refrigerate and soak overnight. Drain fully.
Combine all sauce ingredients (including ½ cup water, but not including the optional shredded cheese or macaroni noodles).
Blend in a blender or with an immersion blender until completely smooth.
Transfer to a small pot and heat to your desired temperature, stirring optional cheese shreds in at the end.
Taste, and add extra seasonings (onion, salt, nutmeg, pepper) if desired. I like to add another ½ tsp salt and a pinch more nutmeg.
If using, cook the pasta according to package directions.
You can serve the sauce over noodles, rice, spaghetti squash, toast, or roasted vegetables.
