Soak a bunch of shiitake mushrooms.
Take a head of garlic, and a large sweet yellow onion. Peel and chop both.
Saute garlic and onions in olive oil, good oil, please. Add sea salt or tamari, and fresh ground pepper.
While the onion and garlic and frying, take off the stems of the mushrooms and chop the caps, and strain and reserve the soaking liquid. If you had time to kill, you could do the mushrooms earlier and use the stems to make a rich broth with tamari.
Add the mushrooms to the garlic and onion and saute some more.
After a while, take the soaking liquid with some flour blended in with it and stir in, and let cook a bit, adding more water or veggie broth or more flour if necessary to make the right texture. Cook until smooth, glossy and no floury taste remains.
Voilá!