In a large bowl, combine the ground beef, egg, bread crumbs, black pepper, salt, onion powder, minced garlic, and Worcestershire sauce. Mix until well combined.

Form the mixture into 4-6 patties.

Heat olive oil in a skillet over medium-high heat and cook patties for about 4-5 minutes per side until cooked to desired doneness. Remove and set aside.

In the same skillet, add the sliced onions and cook until caramelized, about 5-7 minutes.

Sprinkle flour over the onions, stir for about 1 minute, and gradually whisk in the beef broth. Simmer until thickened for 3-5 minutes. Season with salt and pepper to taste.

Return the hamburger steaks to the skillet and simmer in the gravy for a minute before serving.