In a large mixing bowl, combine lean ground beef with breadcrumbs, beaten egg, Worcestershire sauce, ground black pepper, salt, onion powder, and garlic powder. Mix gently until well combined.

Divide the mixture into 6 equal portions and shape into patties, about 1-inch thick. Create a small indentation in the center of each patty.

Heat vegetable oil in a large skillet over medium heat. Once shimmering, place the patties into the skillet. Cook for 4-5 minutes on each side until browned.

Preheat your oven to 300°F. Once preheated, place the plate of patties in the oven for 15 minutes to ensure they are fully cooked through.

In the same skillet, lower heat to medium-low and add butter. Once melted, whisk in flour, cayenne pepper, garlic powder, and onion powder to create a roux.

Gradually whisk in milk, ensuring to dissolve lumps from the roux. Simmer for 2-3 minutes until thickened.

Return the cooked hamburger patties to the skillet with the gravy, ensuring they are well-coated. Let simmer for an additional 2-3 minutes.