Boil the penne with the leek in a large pan of salted water following pack instructions, until al dente.

Meanwhile, heat the oil in a large pan over a medium-high heat and fry the tomatoes for a few minutes, until they start to burst and soften. Add the sweetcorn and cook for 2-3 mins to heat through. Drain the pasta and leeks, reserving a little of the pasta water. Tip the drained pasta and leeks into the pan with the tomatoes, then toss through the ricotta and tuna.

Season with plenty of black pepper. If you want to loosen the consistency, stir in some of the reserved pasta water along with the chopped basil. Serve scattered with the whole basil leaves.