Bring a large pot of water to boil. Season with salt. Add pasta. Cook for 8-10 minutes or until al dente. Reserve 1 cup pasta water. Drain. Set aside.
Meanwhile, heat oil in a large frying pan or skillet over medium-high heat.
Add garlic, onions, carrots and celery. Sauté, stirring occasionally, for about 5-6 minutes or until the onions are soft and the vegetables are tender.
Add tomato passata, Italian seasoning, vegetable broth (stock), bay leaves and reserved pasta water. Stir to combine. Season with salt and pepper.
Cook, covered, for about 15 minutes.
Stir in lentils. Cook for another 10 minutes.
To serve, divide pasta among serving bowls. Add lentil bolognese.
Garnish with chopped parsley and parmesan (if using).