In a dry frying pan and cook the bacon on a medium heat to remove excess salt. Set the bacon aside on kitchen towel and wipe the frying pan clean.

Heat the olive oil in the frying pan and cook the bacon until beginning to crisp. Set the bacon aside on fresh kitchen towel.

Add the onion to the pan and fry gently for 4 minutes. Only stir if necessary to avoid sticking.

Add garlic and fry for another 4 minutes, add the chili, tomatoes, tomato purée, sugar, bay leaf and oregano, stirring thoroughly and cook on a medium heat for 10 minutes. Half-fill the tomato tin with cold water (or optional wine), swirl around and add. Return the bacon to pan, stir thoroughly and cook for a further 10 minutes. Remove and discard the bay leaf. Season to taste. If you want a slightly more liquidy sauce, add a little of the pasta water before you drain it (Step 5 below).

Meanwhile, cook the pasta according to instructions, drain in a colander and toss the butter in. Serve immediately onto warmed pasta dishes, cover the pasta with the sauce and sprinkle with Parmesan.