Place beans, potatoes, ham, onion, water, and salt in pressure cooker. Lock lid into place. Over high heat, bring to pressure, reduce heat just enough to maintain pressure, cook 5 minutes. Quickly release the pressure. Carefully remove lid. Sift together flour, salt, pepper, milk until smooth. Add to cooker. Cook over medium heat until thickened and bubbly. Cook and stir for 1 minute more.
Yield: 6 servings (10 C.)