Cut the courgette into small cubes.
Heat the olive oil in a large frying pan and fry the courgette over a medium-high heat for 6 minutes, until golden but still with a little bite. Season with salt and pepper.
Meanwhile, cook the tortellini in a large pan of salted water for 13 minutes. Reserve around 100ml of cooking water before draining.
While the tortellini are cooking, put the ricotta in a small bowl with the lemon zest, chopped basil and olive oil. Season with a pinch of salt and black pepper and stir until smooth and creamy.
Add the butter and garlic to the courgette and fry for 30 seconds. Add 100ml of tortellini cooking water and cook briefly to create a light, glossy sauce. Take off the heat and stir through the Parmesan.
Add the drained tortellini and gently toss everything together.
Divide between two plates and dot spoonfuls of the lemon-basil ricotta over the tortellini. Finish with fresh basil leaves, a little extra lemon zest, freshly ground black pepper and a drizzle of olive oil.