01 -
Place frozen meatballs, ketchup, light brown sugar, beef broth, yellow mustard, Worcestershire sauce, and onion powder into a slow cooker of 3-quart capacity or larger. Stir to combine.
02 -
Cook on high setting for 2 to 2.5 hours or on low setting for 3 to 4 hours, until sauce is heated through and flavors are well integrated.
03 -
Switch slow cooker to warm mode and serve meatballs. Garnish with freshly chopped parsley if desired.