The winged bean, also known as the Goa bean, four-angled bean, four-cornered bean, Manila bean, and dragon bean, is a tropical legume plant native to New Guinea. It grows abundantly in the hot, humid equatorial countries of South and Southeast Asia. The various parts of winged beans are a rich source of protein, vitamins and minerals. These beans are an especially good source of Vitamin A. This is one vegetable that offers a complete dose of nutrients to the body.