1. In large pot or Dutch oven, heat the olive oil over medium heat. Add the sausages and cook, stirring occasionally, until browned and cooked through, about 8–10 minutes. Using a slotted spoon, transfer the sausages to a plate and set aside.
2. If the pot looks dry, add another drizzle of olive oil. Add in the onion, carrot, celery, garlic, and bay leaves, along with a pinch of salt. Sauté until the onions are translucent and the vegetables are softened, about 5 minutes.
3. Pour in the wine, stirring to scrape up any browned bits from the bottom of the pot. Let it simmer for 2–3 minutes, allowing the alcohol to cook off and the flavors to concentrate.
4. Stir in the lentils, ensuring they’re well coated in the aromatics. Add the broth and tomatoes, along with any juices from the can. Add 1 teaspoon of salt and 1/2 teaspoon pepper. Stir to combine, and bring the mixture to a boil over medium heat. Reduce the heat to a gentle simmer, cover partially, and cook until the lentils are tender, about 1 hour. Check occasionally, and if the soup thickens too much, add additional broth or water as needed.
5. While the soup simmers, slice the cooked sausage into ½-inch slices. (You can then slice them again into half-moon shapes if you prefer smaller chunks.)
6. Once the lentils are tender, stir the sausage and any accumulated juices back into the pot. Simmer for about 10 minutes to allow the sausage flavors to meld into the soup.
7. At the very end, add the red wine vinegar, stirring to incorporate. Remove the bay leaves if desired. Taste and adjust seasonings as necessary.
8. Ladle the soup into bowls and finish with a hearty drizzle of your best quality extra virgin olive oil. Sprinkle generously with freshly grated Parmigiano-Reggiano. Serve!

A favorite variation:

For a pop of color and nutrients; Add a few cups of chopped kale or spinach to the pot near the end of cooking.  You may need to add a bit of additional stock if the leaves make the soup too thick.