Cut lamb into 3 inch cubes.
Melt butter in a saucepan or casserole, add meat and onions, and brown well over moderate heat.
Remove ends and strings from beans and slit lengthwise.
Add tomato sauce, water, string beans, dill or parsley, and salt and pepper.
Bring mixture to a boil, cover, and simmer for 1 1/2 to 2 hours or until meat is tender.