Lentils with Andouille Sausage Recipe

Name: Lentils with Andouille Sausage Recipe
Ingredients: 1 1/2 tablespoons olive oil; 4 whole andouille sausages, pricked all over with a toothpick or cake tester (about 1 pound, see note); 1 large carrot, peeled and diced (about 1 1/2 cups); 1 celery stalk, finely diced (about 1 cup); 1 medium onion, finely diced (about 1 1/2 cups); 1 serrano or jalapeño pepper, minced (optional, about 2 tablespoons); Kosher salt and freshly ground black pepper; 1 cup dried green lentils; 3 1/2 cups low-sodium homemade or canned chicken broth; 2 tablespoons fresh lemon juice from 1 lemon; Extra-virgin olive oil, for drizzling (optional); ½ cup chopped fresh parsley leaves