Heat 2 tbsp olive oil and 2 finely chopped large garlic cloves in a saucepan over a low heat and cook gently for 1 minute. Add 2 x 400 g/14 oz cans chopped tomatoes, 1 tbsp tomato purée/paste and 1 tsp sugar. Stir well until combined, then add 1 large bunch of basil (leaves and stalks). Bring to a gentle boil, then turn the heat down to low and simmer for 15–20 minutes, part-covered, until reduced and thickened. Remove the basil and season with salt and pepper to taste.