Ground sirloin and frozen vegetables make this main dish soup fast and easy to prepare.
In a large saucepan, heat oil over medium heat and add onion. Cook until soft, about 5 minutes. Add ground beef and cook, breaking up chunks with a spoon, until cooked through, about 5 minutes.
Place flour and 2/3 cup water in a jar with a tight-fitting lid and shake to blend well. Pour into saucepan with beef and add broth; bring to a boil, stirring constantly. Add vegetables and simmer until cooked, about 10 minutes. Stir in Worcestershire sauce.