Heat the olive oil in a large frying pan over a medium heat and, once shimmering, crumble in the sausagemeat. Cook for 5-6 mins until the sausage is golden and has released its oils. Remove to a bowl. Scatter the onion into the pan and cook for 10-12 mins, or until completely softened.

Cook the pasta in a large pan of boiling salted water following pack instructions. Drain, reserving a mugful of the cooking water.

Add the garlic, chilli flakes and fennel seeds to the onions and cook for 2-3 mins, then return the sausagemeat to the pan. Add the cooked pasta and reserved pasta water, then sprinkle in the parmesan and mix well until the mixture has emulsified and the pasta is coated in a smooth, glossy sauce. Scatter over the parsley and lemon zest, then squeeze over some lemon juice and season generously with black pepper.