1 tablespoon olive oil
2 cups chopped yellow onions
1 garlic clove, minced
6 cups (or more) water
2 cups lentils, rinsed
2 cups diced carrots
2 cups sliced fresh mushrooms
1 cup diced celery
1 bay leaf
1 teaspoon dried rosemary, optional
Pinch of dried, crushed red pepper flakes
Salt and pepper

1 cup chopped seeded plum tomatoes or 3 ounces of tomato paste
1/2 cup chopped watercress or parsley (optional)

Heat oil in heavy large saucepan or Dutch oven over
medium heat. Add onions and saute until golden, about
10 minutes. Add garlic and stir 2 minutes. Add water
through red pepper and bring to a boil. Reduce heat to
medium, cover and simmer until lentils and vegetables
are tender, adding more water if soup is too thick, about
45 minutes. Discard bay leaf. Add tomatoes to the soup;
simmer 5 minutes.
Season to taste with salt and pepper.

Ladle soup into bowls. Sprinkle with watercress or parsley, if desired.

Serves 4