Follow these straightforward steps to create your delicious Amish Hamburger Steak Bake:

1. Preheat Oven: Begin by preheating your oven to 350°F (175°C).
2. Cook the Beef: In a large skillet, heat olive oil over medium heat. Add the ground beef, diced onion, and minced garlic. Cook until the beef is browned, breaking it apart as it cooks.
3. Add Mushrooms: Stir in the sliced mushrooms and cook for an additional 5 minutes until they soften.
4. Create the Gravy: Sprinkle flour over the beef mixture, stirring well to combine. Gradually add the beef broth, Worcestershire sauce, and soy sauce. Bring to a simmer, allowing it to thicken.
5. Incorporate Vegetables: Add the frozen mixed vegetables, followed by salt and pepper. Stir well to combine and remove from heat.
6. Assemble the Bake: In a greased baking dish, spread the beef mixture evenly. Top with prepared mashed potatoes, smoothing them out across the surface.
7. Add Cheese (Optional): If desired, sprinkle shredded cheddar cheese over the mashed potatoes for an extra layer of flavor.
8. Bake: Place the dish in the preheated oven and bake for 40-50 minutes, or until heated through and the top is golden brown.
9. Cool and Serve: Allow the dish to rest for a few minutes before slicing to serve.

By following these simple steps, you’ll create a hearty meal that everyone can appreciate.