Place the tomatoes in a large oven proof dish, and sprinkle a good couple of pinches of salt and pepper. Bake in a moderate oven for about half an hour. Set aside

In a saucepan, heat the olive oil then add onion and garlic, cooking until translucent.

Add vegetable stock, basil leaves, tomatoes and sugar, bringing the mixture to the boil.

Once cooled, blend and serve.