In a large mixing bowl, combine ground beef, breadcrumbs, milk, diced onions, beaten egg, garlic powder, onion powder, salt, and pepper. Mix gently until all ingredients are evenly incorporated.

Divide the mixture into 4 equal portions and shape each into an oval patty about 1 inch thick. Press a small dimple in the center of each patty to ensure even cooking.

Heat olive oil in a large skillet over medium-high heat until shimmering.

Carefully add the patties to the skillet, ensuring there is space between them. Cook for 4-5 minutes per side until they are browned and cooked to 160°F internally.

Remove the patties from the skillet and set them aside on a plate without cleaning the pan.

In a small bowl, whisk together beef broth and flour until smooth.

Pour the broth-flour mixture into the skillet and bring it to a simmer, whisking constantly.

Cook and whisk for 3-4 minutes until the gravy thickens to your desired consistency.

Return the hamburger steaks to the skillet with the gravy and simmer for 2-3 minutes.

Sprinkle with chopped fresh parsley and serve hot.