In a large mixing bowl, combine the ground beef, finely chopped onion, minced garlic, breadcrumbs, egg, Worcestershire sauce, salt, and pepper. Mix gently until well combined, ensuring not to overwork the meat. Form the mixture into 4-6 evenly shaped patties, about ¾ inch thick. Set the patties aside while you heat your skillet.

Heat a skillet over medium-high heat and add a drizzle of oil. Once the oil is shimmering, carefully place the patties in the skillet. Cook for 4-5 minutes on each side, or until a nice brown crust forms and the internal temperature reaches 160°F (70°C). Once browned, remove the patties from the skillet and set them on a plate.

In the same skillet, reduce the heat to medium and pour in the beef broth, scraping up any browned bits from the bottom—this adds incredible flavor to your gravy. Allow the broth to come to a gentle simmer. If you prefer a thicker gravy, whisk in flour and stir continuously until smooth and well combined.

Preheat your oven to 350°F (175°C). In a baking dish, arrange the cooked patties in a single layer. Pour the rich gravy over the patties, ensuring they are well covered. If desired, sprinkle shredded cheese and frozen vegetables over the top for added flavor and nutrition.

Cover the baking dish with aluminum foil and place it in the preheated oven. Bake for 20-30 minutes, allowing the flavors to meld and ensuring the patties are thoroughly cooked. To achieve a golden cheese topping, uncover the dish for the last 5-10 minutes of baking.

Once baked, remove the casserole from the oven and let it cool for a few minutes. This Amish Hamburger Steak Bake is perfect served alongside creamy mashed potatoes or a fresh side salad.