Put 2 cups diced potatoes, 3/4 cup finely chopped onion and 1/2 cup chopped celery in a large pot. Add 2 1/2 cups boiling water and 1 teaspoon salt and cook. Meanwhile in medium saucepan melt 4 tablespoons buttter , then add 4 tablespoons flour and 1/2 teaspoon dry mustard. Stir and cook for a minute or so. Add 2 cups milk and 1 1/2 teaspoons Worcestershire sauce and stir until it thickens. Add some fresh ground pepper.
Add the milk mixture, 1 cup canned whole tomatoes cut into chunks, and 1 tablespoon parsely (I didn't have any) to the cooked vegetables. By the time you've got the milk ready the vegetables are cooked enough. Add 1 cup grated cheese. I prefer sharp cheddar but this time I used mozzerella because that's what I had. Stir occasionally until it's hot and ready to serve. Ladle into soup bowls and it's ready to eat. My husband likes lots fresh ground pepper on his. A nice hot meal to warm us on a cool fall day.
Hope you had a good weekend.