Vietnamese Culture Dictionary Water Chestnut - Vietnam Traditional Food Posted on December 10, 2015November 8, 2018 by Stephen 10 Dec Water Chestnut (Củ Ấu) is an aquatic plant with white flowers. The cooked fruit has a fragrant, buttery taste. When the leaves rise at an angle to the surface of the water, the fruit is ripe for harvesting. Water Chestnut (Cu Au) Stephen Waterfalls in Vietnamese Culture War Memorial in Vietnamese Culture