Cook pasta in a large pan of boiling, well salted water. Meanwhile, fry the spring onions and chilli in a generous amount of olive oil (about 3 – 4 tbsp) until softened, stirring frequently.
Then add the garlic and fry for a minute or two. Add the tomato and a pinch of salt. Allow to bubble for 2-3 mins. Add tuna and stir. Then add rocket, parsley and a generous ginding of black pepper. Stir through and add the juice of the quarter lemon and about a tablespoon of the cooking water from the pasta.
Check for seasoning.
Drain pasta and add to the sauce. Mix well and serve scattered with the basil leaves.