In a large saucepan on a medium – high heat, bring the olive oil to heat and fry the garlic and onion for 3 minutes, while stirring often, until fragrant and translucent.
Add the stock, cream, broccoli and pasta to the pot and stir well. Bring the stock to the boil. Once boiling, reduce the heat to medium. Stirring occasionally, keep the water at a rapid boil for 8 minutes or until 80% of the liquid has been absorbed by the pasta and the pasta is cooked el dente.
Reduce the heat to low and stir through the mozzarella and parmesan until the sauce is silky. Serve immediately.