Step 1

Heat the oil in a saucepan and gently cook the onion and garlic until softened. Stir in the tomatoes, chilli flakes, balsamic vinegar and sugar. Bring to a simmer and cook slowly for 45 minutes-1 hour. Stir in the basil and season with salt and pepper. This can be left chunky or blended in a food processor for a smooth sauce.

Step 2

Serve spooned over cooked pasta with plenty of parmesan cheese.