Heat the oil in a large pot over medium heat. Sauté onions, carrots, and celery until they soften and start flirting with golden brown. About 5–7 minutes.
Add garlic and cook for another 30 seconds, until the kitchen smells amazing and you’re officially hungry.
Stir in lentils, crushed tomatoes, broth, oregano, thyme, and bay leaf. Bring to a boil, then reduce to a simmer.
Cover and simmer 25–30 minutes, or until lentils are tender. Stir occasionally so nothing sticks and burns like a bad idea.
If you’re using greens, stir them in now and cook 5 more minutes until wilted. Season with salt and pepper to taste.
Remove bay leaf. Add a squeeze of lemon juice if you like a bright finish. Serve hot and proud.