Peel and chop onion and garlic and cook with the basil in oil, until soft but not brown - about 10 minutes.
Wash rice and add it, the bay leaf, and half the tomato juice to the mixture and bring to the boil. Turn heat very low and simmer for 30 minutes. Add walnuts with lemon juice and season with salt, pepper and sugar, adding more tomato juice if necessary to make a soft consistency.
Wash and seed peppers. Put 5cm water into a pan, large enough to take the peppers. Bring to boil, add peppers and remove from heat. Leave to stand, with lid on the pan, for 5 minutes. Then drain and fill with stuffing.
Put on large ovenproof dish. Add a pinch of salt and sugar to the remaining tomato juice and pour around the peppers. (Peppers can be left prepared for several hours.)
When ready to cook preheat oven to 160 C / Gas 3. Sprinkle the top of each pepper with crushed cornflakes or breadcrumbs and a little grated cheese.
Bake for 30 to 45 minutes. Serve garnished with fresh parsley and lemon.