- 2 large onions, diced
- 3 tablespoons oil
- ½ pound fresh mushrooms, sliced
- 5 cups water
- 1 teaspoon salt, or to taste
- ⅛ teaspoon white pepper
- 1–2 bay leaves
- 3 tablespoons flour
- 2–3 tablespoons cold water
- 1 tablespoon mushroom soup mix, optional
- 1/2 cup pareve milk (such as rice milk, soy milk or oat milk)
In a soup pot saute onions in oil until transparent. Add mushrooms and cook additional 5 minutes, stirring occasionally.
Add water, salt, pepper, and bay leaves. Cover and bring to a boil. Lower heat and simmer for 10 minutes.
In a small bowl or cup dissolve the flour in cold water until smooth. Pour into simmering mixture. Add mushroom soup mix if desired. Cook an additional 5–7 minutes. Remove bay leaves and stir in pareve milk.
For a hearty meat soup, add 1½ portions of flanken with water, and cook as above.