1.2 kg peeled canned tomatoes
2 tbsp olive oil
1 onion, finely chopped
2 garlic cloves, crushed
6 basil leaves

Process tomato with a hand-held blender until a coarse purée forms, set aside.
Heat oil in a large saucepan over medium heat, add onion and garlic and sauté until tender (8-10 minutes).
Add tomato and basil, reduce heat to very low and simmer until thick and flavours have developed (1½-2 hours).
Season to taste and keep warm.