Step 1Heat about 1 tablespoon of olive oil in a very large saucepan over medium heat. Add the sausages and cook, stirring frequently until nicely browned and cooked through, about 20 minutes.
Step 2Remove the sausages and set aside to cool, then roughly chop. Set aside.
Step 3Add the ham and the bell pepper to the saucepan and cook, stirring frequently, until the ham has browned a bit and the pepper has softened, about 6 to 8 minutes. Remove from the saucepan and set aside.
Step 4Add another tablespoon of olive oil to the pan, then add the onions and cook, stirring often, until softened, about 10 minutes. Add the celery, fennel, garlic and carrots and continue to cook, stirring often, until the vegetables have softened, about 15 minutes. Add another tablespoon of olive oil if the mixture appears too dry.
Step 5Stir in the lentils and 9 cups of water. Add 1/2 tablespoon of salt and pepper to taste.
Step 6Bring to a boil, reduce the heat to medium low and simmer until the lentils are tender, about 1 hour. Add the oregano, basil, marjoram, reserved sausage, ham and bell pepper. Partially cover the saucepan and cook 15 more minutes. Add the spinach, Sherry and balsamic vinegar. Taste and adjust the seasoning.