Easy Swiss Steak

Ingredients:
2 lb round steak, 1-inch thick, fat trimmed
1 Cup reduced-sodium ketchup
1/4 Cup flour
Salt and pepper to taste
1 large Maui onion, coarsely chopped
1 Tablespoon vinegar
Zucchini, bell peppers, mushrooms, and herbs, chopped (optional)

Instructions:

Place a large sheet of heavy foil in a baking pan. Combine ketchup and flour; put half of the mixture in center of the foil. Place steak on ketchup mixture; season with salt and pepper. Top with onion and remaining ketchup mixture; sprinkle with vinegar. Fold edges of foil to tightly seal the steak in the foil. Bake at 450ºF for 1 1/2 hours, or until steak is tender.