Susan's Steak Soup

2 lb. ground beef, browned and drained
4 1/2 c water
1/8 c dried, minced onion
4 stalks celery, chopped (optional)
4 carrots, sliced
2 - 15 oz. cans tomato sauce
1 t pepper
1 T Worcestershire sauce
16 oz frozen mixed veggies
4 T beef base granules
3 med. potatoes, peeled and cubed
1/2 c butter, melted
1/2 c flour

Put first 10 ingredients (through beef base) in a large crock-pot. Cook on low for 5 hours; add potatoes and cook about 3 - 4 hours longer. Make a paste of butter and flour; stir until smooth. Pour into crock-pot and mix well. Cook another hour and serve.