1. Heat the oil in a large saucepan, add the onion and garlic and saut until soft and transparent.
2. Add tomato paste and diced tomato and simmer until the sauce slightly thickens.
3. Add the beans, parsley or mint and seasoning and just enough water to cover. Bring to the boil then reduce the heat, cover and simmer for 10-15 minutes or until the beans are tender. Serve immediately.