1. Heat olive oil in a large frypan over medium heat. Sauté red onion and fennel until softened.
  2. Add garlic, fennel seeds, chilli and capers and sauté for 1 minute.
  3. Add tomato paste, cook for 30 seconds and add chopped tomato. Cook for 5 minutes, adding water if required to achieve a sauce consistency.
  4. Add tinned tuna and stir to combine.
  5. Meanwhile, into a pot of boiling salted water, add pasta and cook according to packet directions reserving some of the pasta cooking water.
  6. Add pasta to the sauce and toss to combine. Season with salt and pepper and stir through the chopped parsley.
  7. Serve with a garnish of fennel fronds and lemon zest.