Thinly slice the onion and garlic. Cut the s tomatoes in half.
Heat the oil in a large frying pan and gently fry the onion until soft.
Add garlic and chilli flakes (if used), stir for 30 seconds.
Add the broad beans, tomatoes and spices, then season with salt and pepper. Add a splash of water and put the lid on. Simmer over low heat for about 8 minutes, until the beans are cooked and the tomatoes have just softened.
Add the Sherry vinegar, turn up the heat and reduce the sauce, until sticky.
Stir in the chopped parsley and serve.