Generally about 15 minutes to cook, but if the kelp has been soaked in water, it can be cooked for 5 minutes. When cooking kelp, it is important to turn it at any time, so that the kelp can be heated evenly. It is important to note that in the consumption of kelp can not be soaked for a long time, usually soaked for 6 hours can be, if the soaking time is too long, the nutrients in the kelp, such as water-soluble vitamins and inorganic salts, etc., will be dissolved into the water, and the nutritional value will be reduced.