Make medium white sauce; set aside. Simmer 1 cup diced potatoes, 3/4 cup chopped onion, 1/3 cup chopped celery, 1/3 cup grated carrots in 1 1/2 cup of water in a 2 quart saucepan. Do not drain. Add 1/4 teaspoons dry mustard, dash of black pepper, 1 teaspoon dry parsley, garlic salt, and plain salt to taste.

SAUCE:

Melt 1/2 stick butter, add 1/2 cup flour and stir. Add 2 1/2 cup milk. Cook until sauce thickens, stir sauce into cooked vegetables, and simmer a short time. If soup is too thick add more milk.