Hearty Potato Soup

This recipe makes the BEST potato soup!

6 medium potatoes, diced (peeling is optional)
2 carrots, peeled and sliced
2 celery ribs, sliced
2 qts water
1 onion, chopped
4 Tbsp butter or margarine
6 Tbsp flour
1 tsp salt
1/2 tsp pepper
1 1/2 c milk

In a lg pot, cook potatoes, carrots, and celery in water til tender, about 20 min. Drain, reserving liquid and setting vegetables aside. In the same pot, saute onion in butter til soft. In a bowl, mix together flour, salt, and pepper; gradually add milk, stirring til smooth. Add flour mixture to pot with onions. Heat, stirring constantly til thickened. Gently stir in cooked vegetables. Add 1 c or more of reserved cooking liquid til soup is desired consistency. Makes 8-10 servings, about 2 1/2 qts.