Cook beef cut up in slices (cooks faster) in water seasoned with salt or use beef broth. Pour milk in a cup and add arrowroot starch (start with 1tbs). Mix and add to boiling beef broth. Keep mixing it until you get the thicker consistency of sauce. If not thick enough, add more arrowroot. Add heavy cream, vinegar to taste, cut up fresh dill and mix in 4 eggs.