Cheese Soup
["2 c. diced potatoes", "3/4 c. chopped onion", "2 c. water", "1/2 c. flour", "1/2 tsp. dry mustard", "3 c. milk", "1/4 lb. grated Cheddar cheese", "1 c. chopped tomatoes", "3/4 c. chopped celery", "2 1/2 tsp. salt", "1/4 c. butter", "1/4 tsp. pepper", "1 1/2 tsp. Worcestershire sauce", "2 Tbsp. parsley flakes"]
["In a large kettle, cook potatoes, celery and onions in salted water for about 15 minutes until tender.", "Set aside."]
["potatoes", "onion", "water", "flour", "dry mustard", "milk", "Cheddar cheese", "tomatoes", "celery", "salt", "butter", "pepper", "Worcestershire sauce", "parsley flakes"]