This recipe is just that: basic. Rehydrating dried mehijiki will take 30 minutes, but if you prep your vegetables during that time, the actual cooking takes only about 15. You'll be rewarded with a comforting, umami-rich side dish with a concentrated savory flavor that can be eaten on its own or used as a topping or mix-in with rice. If you want to embellish, lotus root, soybeans, tofu, and/or leftover chicken all make nice additions. The recipe is easily doubled and keeps for a week in the refrigerator. —Katie Okamoto
4 to 6
4 to 5
medium/large fresh shiitake mushrooms, rubbed clean and destemmed
Cover dried hijiki generously with lukewarm water, at least 1 1/2 cups. Leave for 30 minutes to rehydrate.
While the hijiki is soaking, whisk together the soy sauce, mirin, sake, and sugar in a small saucepan. Heat very gently over low heat to help dissolve the sugar but don't allow the mixture to simmer. Set aside.
After the hijiki has soaked for 30 minutes, drain through a fine-mesh strainer and rinse under cool water, swishing with your hands. Set the strainer over a container to catch the water and allow the hijiki to continue to drain.
While the hijiki is draining, cut carrots into 1-inch-long matchsticks and shiitake mushrooms into slivers, also about 1 inch long. If using other vegetables, aim for about the same size cuts for those as well. The idea is for all the vegetables and the rehydrated hijiki to be similar in size, as for a slaw.
In a large sauté pan (a wide Dutch oven works well, too), heat the oil over medium heat. Add the carrots and mushrooms and any other vegetables you are using and sauté for about 5 minutes, stirring often to prevent browning. The carrots should be al dente.
Add the drained hijiki to the pan. Give the soy sauce mixture a quick whisk to dissolve any sugar that has come out of solution, and drizzle it around the pan. Lower the heat slightly and let cook for about 10 minutes, stirring frequently, until most of the liquid has absorbed.
Turn off the heat. Mix in toasted sesame seeds, if using, and adjust seasoning as desired. Serve at or slightly below room temperature.