Soak Cashews for 2-3 hours (or better overnight), then drain. (Optionally, you can also boil the cashews for 10 minutes or simply use store-bought cashew butter).
Chop potatoes, carrots, onion, and garlic and cook for about 10 minutes, or until the vegetables are soft enough to blend.
In the meantime, cook pasta ‘al dente’ according to package instructions. Drain afterward.
As soon as the vegetables are soft enough to blend, remove them with a slotted spoon from the cooking water and blend them with 175 ml of that cooking water along with the remaining ingredients in a blender for about 2 minutes until smooth and creamy. (The consistency of the sauce depends on the amount of the liquid).
Pour the sauce over your cooked noodles. (Heat up again, if you like).
Serve your mac and cheese with red pepper flakes and fresh parsley in a pasta dish.
As an option, you can place the noodles in a baking dish, sprinkle with bread crumbs and bake at 180 degrees for about 15 minutes.