Chop up a piece of beef, trimming off any veins. Beat in 2 egg yolks and 1 egg, mix well, and form into flat, round patties. Spread with horseradish fried with a grated roll in 1 spoon butter. Sprinkle with flour and a finely chopped onion, squeezed dry. Melt butter in a stewpan, add the patties, and fry on one side. Add about 2 glasses bouillon, cover the pan, and stew slowly. To serve, garnish the patties with fried or boiled potatoes and pour on the strained sauce.
Stewed sauerkraut may be spread on the patties instead of horseradish.