Using 3 separate plates or shallow dishes, set out ingredients for coating. Cover bottom of one dish with flour, one with eggs and the last with bread crumbs. Add salt and pepper to the eggs and beat with a fork to combine.
Trim fat from cutlets and beat them with a small frying pan or large, smooth-surfaced mallet to ensure they are evenly thin (about 1/2 inch) across the cutlet.
Add butter to frying pan and melt. Coat each cutlet on both sides with flour, egg mixture and finally bread crumbs. Place schnitzel in pan and fry at medium-high heat for several minutes. Be sure that you always keep butter in the pan for frying but do not let the pan get so hot that the butter burns.
When the butter creeps up the edges of the schnitzel, it’s ready to flip. Cook until golden brown on both sides and serve immediately. Garnish with a slice of lemon, if desired.