Sargassum muticum is an invasive brown seaweed that has recently found its way to the shores of Ireland. Some Sargassums are consumed fresh, others cooked in coconut milk or a little vinegar or lemon juice. It is smoked-dried to preserve it. Sargassum is also eaten by itself or added to fish and meat dishes. If not strong it can be added to salads after washing, or it can be cooked in water like a vegetable. If the sargassum is strongly flavored it can be boiled in two changes of water.
A second way of cooking Sargassum, such as S. fusiformis, is frying it quickly then simmer it in water with soy sauce and other ingredients for 30 minutes to two hours or more, depending upon the dish. Other areas of the world mix their Sargassum with oil, salt, and green onions and used as filling in dumplings.