1Heat water to boiling in a medium pot; add potatoes. Reduce heat and simmer until potatoes are tender, approx 15 to 20 minutes.
3Add salt, pepper, butter, onions, carrots and green beans; simmer until tender then add peas.
5In a small bowl, stir together half-and-half and flour until smooth; stir into the simmering vegetables. Cook, stirring constantly until the soup is slightly thickened. Serve immediately.