Place potatoes, onion, celery, salt, ... cover securely. Place pressure regulator on vent pipe and ... and butter into soup and simmer, uncovered, to thicken. ... stirring occasionally. 6 servings.
Heat together until boiling 2 ... paste to thicken soup. Season hamburger with salt, ... 2 hours or pressure cook 40 minutes at 10 ... Makes about 30 quarts.