Lily buds can be found dried, packaged in cellophane, in most Asian grocery stores. They are the buds of tiger lilies - the flowers found in many backyards - and are used primarily to add texture to soups, braises, and stir-fried dishes.
They have a powerful smell when dried, which largely dissipates when they are cooked. When buying, look for lily buds that are golden yellow in color; avoid brown buds, which is a sign of age. Before using, soak the dried lily buds in warm water until soft. With a pair of scissors, trim off the fibrous bit at the end of each bud.