Heat the olive oil in a pan over a low heat. Add the shallot and cook for 2 minutes. Add the garlic and chillies and cook very gently for another minute. Tip in the tomatoes and cook for a further 5 minutes then remove from the heat and leave to cool.
When completely cool, stir through the balsamic vinegar and fresh coriander and season with freshly ground black pepper.
Cook's tip: you can make this dip the day before you want to use it and keep it in a sealed container in the fridge for up to 24 hours.