Low-GL Sauce: Quick tomato sauce

2 tablespoons olive oil
1 onion finely chopped
1 garlic clove finely chopped
1x200 can chopped tomatoes
1 tablespoon lemon juice
1 tablespoon tomato puree
freshly ground black pepper
2 tablespoons chopped fresh herbs, such as parsley, coriander or basil

Heat the oil in a heavy-based saucepan and add the onion and garlic. Cook gently for about 5 minutes, until softened but not coloured. add the tomatoes, lemon juice, tomato puree and black pepper, bring to theboil and simmer for 10-15 minutes, until the sauce has thickened. STir in the chopped fresh herbs.