Cassia is an aromatic bark, similar to cinnamon, but differing in strength and quality. Its bark is darker, thicker and coarser, and the corky outer bark is often left on. The outer surface is rough and grayish brown, the inside barks is smoother and reddish-brown. It is rolled from both sides toward the center so that they end up resembling scrolls. It is native to Burma and grown in China, Indo-China, the East and West Indies and Central America. The pieces are hard and tough, so they are very difficult to grind. They can be used whole in stews and casseroles as the bark will flatten during cooking. The buds are also used whole. To keep them fresh: store it in airtight containers.