On the stove: Heat ¼ cup olive oil in a large pot, add the sausage, onion, celery, carrots, garlic, salt, and red pepper flakes. Cook until vegetables soften. Add lentils, bay leaves, tomatoes, water, salt, and black pepper. Simmer until lentils are tender. Add chard and cook until tender. Discard bay leaves.
In an InstantPot: Use sauté function to cook sausage and vegetables. Add remaining ingredients, lock the lid, set to high pressure for 15 minutes. Natural release for at least 10 minutes. Use sauté function to bring to simmer, then add greens and cook until wilted.
To finish, drizzle remaining olive oil and garlic over soup bowls, top with Romano cheese. Leftovers can be kept in the fridge.
