Heat oil in large saucepan over medium heat. Add celery, onion and garlic and cook until softened, about 5 minutes.
Stir in seasonings, vegetable stock, tomatoes, Bio-Bud lentils and a couple ounces of lemon juice for taste.
Bring to a boil, reduce heat and simmer covered for 5 minutes.
Stir in spinach leaves until wilted, about 30 seconds.
Serve with Parmesan, if desired.