Peel onion, mince, fry with a part of oil. Chop mutton. Mix onion with mutton, an egg, breadcrumbs, milk, salt and pepper, stir well up.
Shape balls, press a little, cover them with flour.
Fry the steaks in heated oil both sides for some minutes. Then reduce the heat and cook until done.
Whisk butter with chopped dill, refrigerate.
When serving, put prepared butter pieces on each beefsteak, garnish with fried onion, fresh vegetables and cooked asparagus.