Lentil Soup With Italian Sausage And Escarole

Ingredients

• 1 2/3 cups lentils (11 ounces), rinsed well
• 5 cups water
• 3 1/2 cups reduced-sodium chicken broth
• 1 turkish or 1/2 california bay leaf
• 4 garlic cloves, finely chopped, divided
• 2 tablespoons extra-virgin olive oil
• 1 pound sweet italian sausage links, cut into 1-inch pieces
• 1 medium onion, finely chopped
• 2 medium carrots, finely chopped
• 2 celery ribs, finely chopped
• 2 tablespoons tomato paste
• 1/2 pound escarole, chopped (4 cups packed)
• 1 to 2 tablespoons red-wine vinegar
• accompaniment: croutons