Copycat recipes for Carrabba's lentil sausage soup are featured at Allrecipes.com and Epicurious. Key ingredients for this soup include sweet Italian sausage, dry lentils, diced tomatoes and chicken broth.
To make lentil and sausage soup from Allrecipes.com, in a large pot, cook 1/2 pound sweet Italian sausage until browned. Add 1 large chopped onion, 1 stalk chopped celery and 1 tablespoon chopped garlic, cooking until tender and translucent. Rinse 1 package dry lentils, and add to mixture along with 1 cup shredded carrot. Pour in 8 cups water, 2 cans chicken broth and 1 can diced tomatoes, stirring to blend. Add 1 tablespoon each garlic powder and fresh chopped parsley, 2 bay leaves and 1/2 teaspoon oregano.
Continue seasoning with 1/4 teaspoon each dried basil and thyme, 1 tablespoon salt and 1/2 teaspoon black pepper. Bring mixture to a boil, reduce heat and cover. Simmer for two and a half to three hours.
To make Carrabba's Sausage and Lentil soup from Epicurious, brown sausage, but don't drain cooking juices. Add sausage and sausage juices to a large pot along with 1 each chopped small onion, chopped celery stalk, chopped carrot and chopped small zucchini.
Pour in 1 carton chicken broth and 2 cans no-salt-added diced tomatoes. Stir in 3 garlic cloves, 1 teaspoon salt and 1-1/2 cups dry lentils. Season with 1/2 teaspoon each black pepper, red pepper flakes, basil, oregano, parsley and thyme. Bring to a boil, reduce heat and cover. Simmer for one hour, and sprinkle 1/4 cup shredded Parmesan cheese on top before serving.