Cooking Day: In a large stockpot, brown ground beef with onion and celery until vegetables are tender and meat is cooked. Drain. Add 1 can beef broth, steak sauce, Worcestershire sauce, salt and pepper. Bring to a boil, then reduce heat and simmer for 20 minutes.
In a separate bowl, mix flour and remaining can of beef broth . Once flour and broth are mixed well, add to soup and continue stirring until soup is bubbly. Cook for an additional minute. Stir in mixed vegetables and diced tomatoes.
Cook completely and freeze in gallon size freezer bag(s). Date, label and freeze.
Serving Day: Thaw completely. Place soup in stockpot. Bring to a boil, then simmer until vegetables are tender and soup is heated through, about 20 minutes.