Heat the oil in a small pan, add the onion and pepper, and fry gently until soft, about 10-15 mins. Crush half the garlic and add this to the pan, along with the tomatoes, paprika, vinegar, beans, sugar and some seasoning. Bring to a simmer and cook for 10-15 mins or until slightly reduced and thickened.
Toast the bread, rub with the remaining garlic and drizzle with a little oil. Spoon the beans over the toast, drizzle with a little more oil and scatter over the parsley.