Also called bean threads or glass noodles, these noodles are made from the starch of mung beans. These dried, translucent noodles must be presoaked before using in most recipes unless they are added directly to soups or simmering liquids. The dry noodles also can be deep-fried; they puff up instantly and dramatically to a size many times larger than when dry. You can substitute rice stick noodles if you can't find cellophane noodles.