1 pound lean ground beef
1 small onion, finely chopped
3/4 cup Italian-style bread crumbs
2 large eggs, beaten
3 tablespoons Worcestershire sauce
1 tablespoon red wine vinegar
3/4 teaspoon salt
1/2 teaspoon ground black pepper
Preheat oven to 350°F (175°C). Spray a 12-cup muffin tin with vegetable cooking spray.
Gently combine beef, onion, bread crumbs, beaten eggs, Worcestershire sauce, vinegar, salt and pepper in a large bowl; mix well. Fill 8 of the 12 cups up to the top with meat mixture. Fill the remaining 4 cups with water to prevent burning while cooking.
Bake for 20 to 25 minutes or until browned on top and thoroughly cooked. Immediately remove from tin and serve.
Makes 8 servings.