Heat a pan with the oil and gently cook the onion for 3 minutes, or until it is soft without being coloured.
Add the garlic, basil stalks, thyme, bay leaf, tomato paste and the fresh tomatoes. Season with the sugar, salt and black pepper. Pour in the chicken stock and bring to the boil, reduce the heat, cover and simmer for about 15 minutes. Discard the bay leaf.<