Use any combination of chantrelles, cremini, white, enoki, shitake, porcini mushrooms. Dried mushrooms of any variety may be added or substituted. If soaking mushrooms, cover with water and let sit for 30-40 minutes. Squeeze out excess water. Clean mushrooms and slice thinly.
Melt margarine in a large pan and add onion, garlic and mushrooms. Cook over medium heat for 10 minutes.
Add all other ingredients and mix well (use a whisk for the flour). Continue cooking until well mixed and completely cooked, about 10-15 more minutes. Serve over cooked fettucini. Sprinkle with scallions or parsley for garnish.