Amana-Style Swiss Steak

1 1/2 pounds lean beef steak
1 1/2 tablespoons shortening
1/4 cup all-purpose flour
3/4 teaspoon salt
Pepper to taste
1/2 cup vinegar
1 medium onion, chopped

Combine flour, salt and pepper; pound into steak. (Meat may be cut into serving pieces, or not, as desired.)

Melt shortening in a large skillet and brown steak light on both sides. Add vinegar and cook just until liquid evaporates. Add chopped onion and cover with water.

Cover skillet and simmer until meat is tender (about 2 hours). If necessary, add more water during cooking. Cooking liquid may be thickened with flour before serving, if desired.