Preheat oven to 200°C.
In a large ovenproof dish, combine garlic, tomato paste, cream, stock, diced tomatoes, salt, and onion. Stir to combine. Add pasta and mix to coat with sauce, then sprinkle chilli flakes on top.
Cover tightly with foil and bake for 40 minutes (leave longer if pasta is still firm).
Remove foil, stir gently, then sprinkle half the parmesan and stir through. Top with remaining parmesan and bake uncovered for 12–15 minutes, until pasta is tender and cheese is golden.
Serve hot and enjoy.
