Heat most of the oil in a large frying pan over a medium heat. Fry the aubergine for 10-12 mins, stirring occasionally until golden brown and soft. Stir in the garlic and chilli, and cook for 2 mins more until fragrant. Tip in the tomatoes, then swill out the can with a splash of water and pour that in too. Stir in the vinegar, sugar and tied basil stalks, then season well. Simmer for 15 mins, stirring occasionally until thick and saucy.
