Soak the saffron in 1 tbsp boiling water and set aside.
Heat the oil in a large frying pan with a lid and fry the onion for 5 minutes, add the garlic and fry for 2-3 minutes. Stir in the rice and paprika.
Stir in the chopped tomatoes, pepper, Walnuts, saffron liquid, green beans and butter beans and add half the stock, cover and simmer gently for about 25 minutes, stirring occasionally, gradually adding the remaining stock until the rice is just tender, season and stir in the parsley.
