I love this dish and so does everyone who tastes it !! The original recipe called for slow cooking for 6 to 8 hours. Mine always seems to be done between 4 and 6 hours. I suggest you test the tenderness of the meat at 4 hours.
In a large bowl, combine flour, onion powder, garlic powder, salt and pepper. Dredge sirloin pieces lightly in flour. Heat oil in skillet, brown beef on all sides.
Place browned beef into crock pot. In a small bowl, combine soup, onion soup mix, beef broth and Worcestershire sauce. Mix well. Add water, beef cube and salt and pepper, to taste. Stir well. Pour over beef
Cook on LOW 6 to 8 hours until gravy is thick and beef is cooked through and tender.
Serve over cooked egg noodles, rice or mashed potatoes. Garnish with parsley, if desired.