In a mixing bowl, combine ground pork, ground beef, bread crumbs, milk, Worcestershire sauce, onion, garlic, black pepper, salt, egg and sugar.
Mix thoroughly and form into patties on a wax paper. Freeze for at least 30 minutes or more.
In a non-stick pan or stove top grill, cook the patties for at least 3 minutes on each sides or until golden brown. Transfer to a serving dish and set aside to assemble late with the mushroom sauce.
To make the mushroom sauce, saute the mushroom in a pan with a little oil until all sides are seared. Set aside.
Heat a pan and put the oil and butter. Melt the butter until it is hot enough and test by sprinkling a little flour and when it bubbles, it is ready. Then put in the flour. Stir until the mixture turns light brown and turns into a roux or paste.
Pour in the beef broth, salt and pepper and bring to a boil. Stir until it turns into a thick gravy. Put in the mushrooms and stir for a minute.
Pour over the burger steak and serve with steamed rice. Enjoy!