Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
2         tablespoons   olive oil -- up to 3
10        medium        white or brown mushrooms -- washed and thinly sliced
4         ounces        oyster mushrooms -- washed and thinly sliced
2         ounces        shiitake mushrooms -- washed and thinly sliced
1         medium        onion -- diced
2         cups          vegetable stock
1         tablespoon    worcestershire sauce
                        salt and freshly ground black pepper -- to taste

Preparation:

In a large stockpot, heat the oil. Add the mushrooms and onion, cover, and saute‚ over medium heat for 7 to 10 minutes, stirring occasionally. Add the vegetable stock and bring to a boil. Lower the heat to medium and add the Worcester sauce and salt and pepper. Cook for about 30 minutes. Before serving, adjust the seasoning if necessary.