Finely chop the onion and garlic.
Dice the carrot and celery.
In a large, heavy-based pot, heat the oil, then gently sauté the onion, celery and carrots for 5 minutes until soft, then add the garlic and herbs of your choice.
Stir for a minute, then add the passata and the vegetable stock.
Bring to a boil, then add the pasta.
Simmer, uncovered, for 10-12 minutes.
When the veggies are tender, add the drained lentils and spinach then cook for another 3-5 minutes.
Taste the soup and season to your liking.
Serve warm.