Summer in Japan is a lush and verdant season that makes you feel like you're living in an arboretum amidst a soundtrack of humming cicadas. It's against this backdrop that one of Japan's most delightful seasonal traditions developed: cold somen noodles.
These whisper-thin strands of hand-pulled noodles have served as a welcome respite from the heat for centuries. So whether you enjoy scooping nagashi somen up from a bamboo flume of ice-cold spring water or you prefer a somen salad topped with a colorful explosion of summer produce, each mouthful is a testament to the fleeting beauty of summer in Japan.
Why This Recipe Works?
- Because somen noodles are so thin, it's essential to be precise with the time when you boil and chill it.
- Serving the somen noodles in a bowl of ice water makes the noodles nice and cold while preventing them from sticking together.
- The water clinging to the noodles will dilute the dipping sauce as you eat, so you can add more sauce as you eat if it starts to get too thin.
- Having a wide variety of condiments to add to the sauce keeps cold somen noodles interesting to the last bite.
- Dashi - Dashi is a fundamental Japanese soup stock most commonly made with kombu (a type of kelp) and katsuobushi (cooked, smoked, fermented, and shaved skipjack tuna). The combination creates a mildly smoky broth with an intense umami taste that's the signature of most Japanese dishes. There are three ways to make dashi: from granules, from dashi packs, and from scratch, and I go through the pros and cons of all three methods in my How to Make Dashi tutorial.
- Soy Sauce - I like using usukuchi shoyu for my somen dipping sauce. Usukuchi soy sauce is widely used in the Kansai region of Japan, and it has a lighter color and milder flavor thanks to the shorter fermentation time used to produce it. This gives the somen sauce a delicate taste that doesn't overpower the flavor of the noodles. Usukuchi soy sauce is not the same as products marketed as "light soy sauce" in the West, which is usually regular soy sauce brewed with less salt. If you can't find usukuchi soy sauce, you can substitute it with regular soy sauce, but I recommend halving the soy sauce and adding 1 teaspoon of salt.
- Sake - Sake is an alcoholic beverage brewed from rice, but we're interested in the amino acids it contains for this recipe. These give the sauce the taste of umami. Boiling the sauce burns off the alcohol in both the sake and the soy sauce. Another option is to use mirin, but most mirin available outside of Japan is just corn syrup and flavorings.
- Sugar - A small amount of sugar adds a touch of sweetness to the somen sauce, rounding out the savory flavors from the soy sauce and dashi. It also harmonizes with the sake, enhancing its natural sweetness. I used evaporated cane sugar, but if you're avoiding refined sugar, you could use honey, but make sure you use a mild one so it doesn't overpower the flavor of the other ingredients.
- Somen Noodles - Somen (素麺) are very thin hand-pulled Japanese wheat flour noodles with a recorded history dating back at least 700 years (but it's likely much older). Wheat noodles that are less than 1.3 millimeters in diameter are considered somen, noodles that are 1.7 millimeters in diameter or greater are considered udon, and noodles that fall between the two are called hiyamugi. Colored somen can be flavored with ingredients such as umeboshi, yuzu, and matcha.
- Condiments and Toppings - Part of the joy of eating somen is the toppings and condiments you serve with the cold noodles. Traditional condiments include ingredients like green onions, grated ginger, green shiso leaves, sansho pepper leaves (kinome), myoga, toasted sesame seeds, nori, and rice vinegar. These days it's also common to serve somen like a salad topped with colorful ingredients such as tomatoes, ham, and snap peas.
How to Make Somen Sauce
Let's start with the heart of the dish: the dipping sauce or mentsuyu. Pour the dashi, usukuchi soy sauce, sake, and sugar into a saucepan and bring the mixture to a rolling boil. This not only allows the flavors of the ingredients to mingle, but it will also burn off the alcohol in the sake and soy sauce, eliminating any harshness while retaining their flavor and umami. After a minute of intense boiling, remove the pot from the heat and allow the sauce to cool to room temperature before placing it in the refrigerator to chill. If you're in a hurry, you can accelerate this process by placing the pot in an ice bath.
Somen sauce will keep in the fridge for weeks, so you can make a big batch and store it in a sealed container for when you're craving a cold noodle dish.
How to Cook Somen Noodles
Bring a large pot of water to a boil. It's best to use a pot that's wide enough to fit the noodles lengthwise so you don't struggle to submerge them. You also want to make sure you have enough water in there, or the starch released by the noodles as they boil will cause the pot to boil over.
Because somen noodles are so thin, it's super important to use a timer and cook them for exactly the time specified on the package. I usually set the timer with noodles in hand and then drop them into the boiling water as soon as I start the timer. Be sure to stir the noodles so they don't stick together.
If the time is not written in English, look for the character "分"; this means "minutes" in Japanese, so the number next to it will tell you how many minutes you need to boil the noodles (usually 2-3 minutes). Sometimes the package instructions will have two times listed; for example, 2分 and 3分. The shorter time is generally for when you plan to use the noodles in a hot soup, and the longer time is for serving the noodles chilled.
Have a strainer ready and as soon as the timer goes off, strain the somen and rinse them under cold running water until they're chilled. I usually lower the whole strainer into the pot in which I cooked the noodles and fill it with several changes of water, swishing the noodles around to ensure they chill evenly.
How to Serve Somen
Somen noodles are wonderfully versatile and can be served in various ways. Here are three ideas for serving them chilled:
Nagashi Somen - Nagashi somen means "flowing noodles." In this fun summer tradition, somen noodles are sent down a bamboo flume filled with cold water. Guests wait with chopsticks in hand to skillfully catch the noodles as they flow by before dipping them in tsuyu or somen sauce with condiments. My issue with this method is that you share the flume with others. It's not quite as fun, but a more hygienic solution is to simply serve the noodles in a bowl of ice water.
Somen Salad - Another way to serve these is to drain the noodles after they've been chilled and then serve them on a plate topped with a bounty of seasonal vegetables. Think crisp cucumbers, sweet tomatoes, vibrant snap peas, and fragrant herbs and garnishes like scallions, ginger, and shiso. For protein, you can top the salad off with Kinshi Tamago (thin egg ribbons) or thin strips of ham, and I usually like to add a sprinkle of toasted sesame seeds for texture. As for the dressing, I use the somen dashi recipe below, add a little rice vinegar and grated ginger, and pour it on top of everything.
Zaru - Zaru Somen is the most traditional way of serving somen and is named after the zaru (bamboo tray) the noodles are typically served on. I'm not a huge fan of this presentation because the thin noodles tend to stick together after just a few minutes, which makes it hard to pick them up. The upside, though is that the noodles won't water down your sauce like with a nagashi somen.
Serve it With
Depending on how you serve it, cold somen noodles can make for a light lunch or pair with other dishes for a more filling meal. Vegetable side dishes like a sunomono and hijiki salad are two good options, and if you're looking to add a bit of protein to the meal, my Japanese breakfast salmon or onsen tamago are both solid options.
Other Cold Noodle Recipes
- Zaru Soba (cold soba)
- How to make Udon Noodles
- Spicy Cold Sesame Noodles
- Hiyashi Chuka (Cold Ramen Salad)
- Combine 4 tablespoons usukuchi soy sauce, 2 tablespoons sake, 1 teaspoon sugar, and 1 cup dashi stock in a pot, and bring to a rolling boil.
- Boil the mixture for 1 minute to burn off the alcohol, then allow to cool and refrigerate. You can also chill in an ice bath.
- Bring a large, wide pot of water to a boil for the somen noodles.
- Set a timer for the amount of time specified on the somen package (usually 2-3 minutes) and lower the 300 grams somen noodles into the boiling water simultaneously.
- When the timer is up, strain the cooked noodles immediately and rinse under cold water until chilled.
- Serve the cold somen in a bowl of ice water alongside the chilled dipping sauce with various condiments like chopped scallions, grated ginger, shredded nori, and shiso.