In a large bowl place ground beef, eggs, Worcestershire Sauce, bread crumbs, milk, salt, pepper, garlic powder, and onion powder. Mix all together until well combined. (Don't overmix.)
Pat to flatten down the meat in the bowl until it's solid. Using your hand, draw a line down the center of the meat to divide into 2 sections. Divide each section into 3 triangles. This should give you 6 triangle sections. (This helps to create even patties.)
Pull out each triangle section of meat and form into oval shapes. Place on a plate.
In a large skillet heat butter and cooking oil over medium high heat until it starts to sizzle. Place the 6 oval shaped patties into hot skillet and cook on one side for 4 minutes until golden brown. Flip over patties and cook an additional 4 minutes until both sides are browned. Pull out patties from skillet.
Add 6 TBS of butter to the same skillet over medium high heat and allow to melt. (Leave in the bits and a little bit of the hamburger grease, it's flavor.) Add in flour and using a whisk mix and stir for 1 minute. (Mixture will appear to be like a paste consistency, just keep moving it around the skillet for the 1 minute. Slowly pour in the beef broth 1 cup at a time while whisking until flour mixture is incorporated into broth and is smooth. Stir in salt, black pepper, garlic powder and onion powder.
Place hamburger steaks back into skillet with the gravy and cover the steaks with some of the gravy. Lower heat to medium or medium low and simmer for 20 minutes to finish cooking the steaks. Turn off burner. Garnish with parsley and serve over mashed potatoes, rice or cooked pasta.