Japanese Cold Somen Noodles

1. Gather all the ingredients (the garnishes and optional toppings are not shown).

To Make the Dipping Sauce

1. I recommend making Homemade Mentsuyu for the best flavor, but you can also use store-bought mentsuyu. Most are concentrated, and every brand has slightly different instructions on how to dilute it. I explain a bit more on my mentsuyu pantry page. The brand I use recommends a dilution ratio of one part mentsuyu to three parts water, or 1 to 3.
2. Combine ¼ cup mentsuyu (concentrated noodle soup base) and ½–1 cup iced water in a measuring cup and mix well. If your mentsuyu is not concentrated (labeled “straight“ on the bottle), then you don‘t need to dilute it. Tip: Include several ice cubes as part of your measured water to keep your dipping sauce chilled and refreshing.

To Prepare the Garnishes

1. Cut 1 green onion/scallion into thin slices and grate the ginger (I use a ceramic grater) and put them separately in small bowls. I highly recommend shiso leaves (perilla/ooba) and myoga ginger for somen, if you can find them. Thinly slice and place them in separate small bowls. Grate a small amount of daikon radish (optional), gently squeeze some of the liquid out, then place in a small bowl. Pour some toasted white sesame seeds (optional) into a small bowl. Gather all the garnishes on a tray, if desired, and set aside.

To Prepare the Toppings (optional)

1. To make the meal more filling, you can prepare toppings such as chicken chashu, simmered shiitake mushrooms (see next step), blanched okra, toasted aburaage, shredded thin omelette (see How to Make Kinshi Tamago), julienned cucumbers, thinly sliced Satsuma age, and cherry tomatoes. Find more ideas in the blog post.
2. To make the simmered shiitake mushrooms, remove the stems from 8–10 shiitake mushrooms. Cut the caps into thin slices. In a saucepan, combine the mushroom slices, 1 tbsp soy sauce, 1 tbsp mirin, 1 tsp sugar, and 1 tbsp water (or dashi). Simmer, uncovered, until there is almost no liquid left. Set aside to cool.

To Cook the Somen Noodles

1. Bring a large pot of water to a boil. (You do not need to add salt to the water.) Meanwhile, remove all the wrappings from 4 bundles dried somen noodles, as all the noodles should go into the boiling water at the same time. Tip: Somen noodles cook very fast, so it‘s important to work quickly.
2. When the water is boiling, add the somen all at once, spreading the noodles around the pot in a circular motion to separate each strand (I use a motion similar to opening a Japanese folding fan).
3. Cook in the boiling water, stirring occasionally with chopsticks, for 1 to 1½ minutes or according to the package instructions. If it looks like the water may boil over, add a small amount of cold water to the pot. When the noodles are done, drain them in a colander. Tip: I slightly undercook my noodles to keep their springy texture.
4. Next, rinse the somen under cold running water. Once the noodles are cool enough to handle, rinse them with your hands as if you are washing your clothes. Knead and massage the noodles to get rid of the excess oil. When you finish, transfer the somen to a large bowl of iced water with several ice cubes.

To Serve

1. Cold Somen Noodles are often served family style in Japan, either chilled in iced water or on a tray. To serve in iced water, keep the chilled noodles in their large bowl of water with plenty of ice cubes. Decorate with green leaves such as the Japanese maple I used here. Serve the tsuyu dipping sauce in small individual bowls or cups.
2. Alternatively, you can serve the somen on individual plates or a large serving platter. With chopsticks, neatly roll the chilled noodles into small bunches and arrange on your plates/platter (I used a Japanese bamboo serving basket). Place the bowl or tray of somen in the center of the table along with the garnishes and optional toppings you prepared earlier. To eat, sprinkle a few garnishes and toppings into your tsuyu, dip some somen in your sauce, and enjoy.

To Store

1. You can keep the leftovers in an airtight container and store in the refrigerator for up to 2 days. If the noodles stick to each other under refrigeration, run them under cold water to loosen them up before serving. Ideally, you should boil the noodles right before serving so they won't lose their perfectly springy texture.