Lyonnaise Potatoes

2 pounds potatoes, peeled and diced
5 oz butter
4 medium white onions, finely sliced
Salt & freshly ground black pepper
Italian flat leaf parsley, finely chopped

Melt 3 ounces of the butter in a heavy skillet.  Add the potatoes and fry them over medium heat, turning them regularly until they are golden brown and evenly cooked.  In a separate pan, melt the remaining butter and gently fry the onions until they are also golden brown.  Add the onions to the potatoes, mix well and continue cooking.  Sprinkle with the chopped parsley and serve.