Hon-Tsai-Tai Also known as kosaitai. This vegetable has deep purple leaf and flower stalks and dark green leaves. The plant grows vigorously and produces lots of flower buds for vegetable use. Young stalks and flowers are very tender, excellent for stir-fry. This vegetable is tolerant at low temperature and the purple colour intensifies as the temperature decreases. Harvest young leaves and stems with flower buds. Hon Tsai Tai tastes similar to mustard green and broccoli raab, making it perfect for stir fry-dishes, salads and savoury soups.