Preheat oven to 350°F (190°C).
In a high-speed blender, combine sauce ingredients: water, cashews, tomato paste, nutritional yeast, lemon juice, garlic powder, miso paste, tapioca starch, rolled oats, onion powder, mustard powder, and salt. Blend for approximately 2 minutes or until the mixture is smooth and creamy.
In a large pot, cook the macaroni noodles in boiling water according to the package instructions until al dente (approx 8 minutes).
Drain noodles, rinse, and immediately stir in the vegan butter, allowing it to melt and coat the warm noodles thoroughly.
Transfer the buttered noodles to a baking dish, spreading them evenly.
Stir in 16 ounces of the shredded vegan cheese into the macaroni noodles, ensuring it’s well distributed.
Pour the prepared sauce over the macaroni and cheese mixture in the baking dish. Stir to combine.
Top the macaroni and cheese with the remaining 8 ounces of shredded vegan cheese and bake 30-40 minutes, or until bubbling and edges are brown.
Remove from the oven and allow to rest 10-15 minutes before serving.
