potatoes
2 stalks celery
1 large onion diced
salt
pepper
2 tablespoons butter
milk
1/2 cup cornstarch
3/4 cup cold water

Use enough potatoes for desired amount of soup. Peel and cut in small pieces. Cook until tender and drain. Dice onion and celery. Cover with water and cook till tender. Add to potatoes, do not drain, add water and all. Add salt, pepper, butter, and milk. Add enough milk to cover potatoes to make broth for soup. Cook over medium heat until hot. Mix cornstarch and cold water together stir till cornstarch is dissolved. Slowly add to soup until desired thickness is reached. May have to mix another batch of cornstarch and water, depends on desired thickness.