Bring a large pot of salted water to a boil. Add pasta and cook as per packet instructions. Drain and rinse under cold water to stop cooking. Set aside.
In a heavy based saucepan over medium heat, drizzle olive oil and saute onions, garlic, carrots, and celery for 5-6 minutes. Add the mushrooms, lentils and canned tomatoes. Bring to a simmer and cook until sauce has reduced slightly and flavours have infused. Add pasta to bolognese, toss to combine and heat through.
Serve with chopped parsley and grated parmesan cheese.