Bibim Guksu (Korean Cold Mixed Noodles) Recipe

The canon of slurpable Korean cold noodle dishes is vast and varied, with each dish offering a uniquely delicious way to cool down on a blazing summer day. Some, such as the beloved Korean cold noodle soup mul naengmyun, are labor-intensive, multi-step dishes you’d typically order at a restaurant or assemble from a kit purchased at the Korean supermarket. But many, including this spicy, sweet, and tart bibim guksu, are meant to be quick, one-bowl affairs you can mix up with ingredients you might already have, making them a great option for no-fuss meals that are hearty and satisfying but still leave you feeling light.

Bibim guksu is a spicy cold noodle dish that literally translates to “mixed noodles” in Korean. While lots of Korean noodle dishes are mixed, “bibim guksu” generally refers to this specific dish of thin, chewy noodles (typically somyeon) tossed with a gochujang-based sauce. The noodles can be garnished with various toppings such as hard-boiled eggs, roasted sesame seeds, and cooling, crunchy vegetables. You may even see fruit, such as julienned Asian pears or apples.

The very best bibim guksu transcends the sum of its parts: The chilled noodles mingle with the crunchy, juicy vegetables; the boiled egg is substantial and a little rich; and everything is coated in a spicy, slightly sweet gochujang-based sauce that gets an acidic kick from rice vinegar. A shower of fragrant ground sesame seeds and a drizzle of toasted sesame oil add an intensely nutty aroma that draws you to the bowl before you even take a bite. Each crunchy-meets-chewy bite is refreshing and tart from the vinegar, just sweet enough from the honey, and finishes with the slow, lingering burn of the gochujang, which demands to be chased with another cooling bite.

In my research across multiple Korean cookbooks and online resources, no two bibim guksu recipes were exactly alike, which only speaks to the dish’s wildly adaptable nature. Some incorporate chopped kimchi and kimchi juice in the base of the bibim sauce. Some sweeten the sauce with plain white sugar, while others use fruit preserves or even lemon-lime soda. The toppings are infinitely variable. The only constants are bouncy noodles and a balanced sweet-spicy-savory sauce that jolts the palate. My recipe teaches you how to nail both of those constants, while leaving room for your own spins.

The Noodles: All About That Bounce

A proper bibim guksu features firm, silky noodles coated in a slick, glossy sauce that makes it delightfully easy to slurp them down. Bibim guksu is widely prepared with Korean somyeon noodles (also known as somen, somyeon is a thin, round wheat noodle that’s a popular choice for Korean cold noodle dishes.) Somyeon takes just a few minutes to cook, making it a convenient option for those looking to get dinner on the table fast.

There are a few key steps to preparing perfectly cooked somyeon: Constantly agitating the noodles with tongs or chopsticks as they boil prevents them from sticking and getting clumpy. Immediately shocking the noodles in ice water halts the cooking process and firms up the noodles, enhancing their chewy quality. Finally, vigorously scrubbing the noodles with your hands under cold running water washes away every last bit of excess starch, which further ensures they won’t stick to each other and makes it easier to mix them evenly with the sauce. 

A note on the ice bath: I don’t have an ice machine, which makes me very selective about when and where I use my precious human-made ice cubes. During testing, however, I found that shocking the noodles in an ice bath produced noticeably chewier and less sticky noodles than when I shocked them in the coldest tap water I could get. Which is to say: This is the time to bust out the ice—you won’t regret it.

If you can’t find somyeon, try substituting buckwheat noodles, which will add an earthy note to the dish. Any thin, lightweight wheat noodle that clings to sauce well will also work—even angel hair pasta or capellini would be a good substitute. For a gluten-free option, Korean markets sell rice-based somyeon; you could also use rice vermicelli. (Buckwheat is also gluten-free, but many buckwheat noodles also include wheat so be sure to check the label if that’s a concern.)

The Sauce: A Harmony of Flavors

A well-balanced bibim guksu sauce is a harmonious blend of spicy, sweet, sour, and savory flavors, with none dominating another. It could be described in Korean as having the quality of “gamchilmat,” says Irene Yoo, a Korean-American recipe developer and chef of the forthcoming Orion Bar in Brooklyn. Gamchilmat doesn’t have an equivalent word in English and is probably most similar to the Japanese “umami,” but Yoo says it could be described as a “captivating” or “attractive” taste that floods your tastebuds and pulls you in.

The spicy element of bibim guksu sauce is typically anchored by gochujang and gochugaru. Gochujang, one of the three “mother jangs” of Korean cuisine (along with doenjang and ganjang) is a thick, fermented red pepper paste that packs a sweet, deep heat. Gochugaru, or Korean chile powder, brings a bright, fruity spice that adds another dimension of heat to the sauce. Look for gochujang that has rice syrup instead of corn syrup in the ingredients list, as the latter can add an overpowering, cloyingly sweet flavor. As for gochugaru, you want coarse flakes (akin to wheat bran), as opposed to the very finely ground flakes, which are more typically used for making gochujang and for flavoring and coloring soup bases where you don’t want to see the flakes. While you technically could use the finely ground flakes here, the coarse gochugaru is readily available and more traditional in this dish.

Unseasoned rice vinegar brings bright tartness that’s essential to this dish’s gotta-have-another-bite appeal, while soy sauce and sesame oil add savoriness. But the sweetening agent is where you can really let loose and experiment, and this is where you’ll find lots of creative license amongst bibim guksu recipes. In Koreaworld: A Cookbook by chef Deuki Hong and writer Matt Rodbard, for example, bibim guksu sauce is sweetened with a combination of Asian pear, 7-Up, and homemade fruit preserves. After testing many different sweeteners, including regular granulated sugar, brown sugar, maesil cheong (Korean green plum syrup), and corn syrup, I settled on a mix of grated Asian pear and a little honey to provide a well-rounded, complex sweetness that adds to the sauce’s “gamchilmat” quality.

Once mixed, bibim guksu sauce will keep in the fridge for up to two weeks and can easily be doubled or tripled so you can mix up a bowl of noodles at a moment’s notice. You can also use the sauce as a dip for raw vegetables or grilled meats, or mix it into bibimbap.

The Mix-Ins

Fresh vegetables, and even fruits, are a common addition to bibim guksu and provide welcome crunch and juiciness that complement the spicy, saucy noodles. I opted for julienned cucumber, which is a classic, but you could add anything watery or crunchy, such as thin strips of raw bell pepper, blanched bean sprouts, tender lettuces, julienned radish, or matchsticks of Asian pear. It’s hard to go wrong, and you can mix and match to add various colors, flavors, and textures to your bowl. Chopped kimchi is also a great way to add crunch, fermented funk, and extra spice and acidity to your bowl, and is a very popular bibim guksu addition.

My non-negotiable mix-in is a chiffonade of perilla, a tender leaf that’s part of the mint family and has a vegetal, bitter, and vaguely anise-y flavor that is unmistakably Korean. When you get a bite of bibim guksu with the perilla folded in, it cleanses the palate and prepares you for another spicy, sweet bite. Though you can substitute with other herbs that are a part of the mint family, like shiso, the effect will not be quite the same.

Putting It All Together

If there is one codified rule of making bibim guksu, it would be that it must be mixed by hand. This imparts the all-important sohn-mat, Korean for “taste of the hand,” which refers to the unique flavor that only comes from the love and labor of the cook. It’s why, for many Koreans, mom’s truly is always best. To keep the sauce from staining your hands, you can wear a disposable food-safe glove—my parents buy these thin, oversize vinyl gloves by the hundreds for this exact purpose—or just wash your hands well before and after mixing.

I like to serve my bibim guksu with the julienned cucumbers and chiffonade of perilla nicely arranged on top of the saucy noodles, mostly because I like how it looks. But you can toss the vegetables with the noodles when you combine them with the sauce if you prefer. I like to shower my bowl with a generous helping of toasted sesame seeds that I crush in a mortar and pestle to unlock their full flavor potential. (If you’ve only ever topped your dishes with whole toasted sesame seeds, I urge you to try this!) I finish off my bowl with a few drops of good-quality toasted sesame oil (I like the White Sesame Oil from Yun Hai Pantry) because it has a more intense aroma and flavor than mass-produced sesame oil—kind of like finishing off a pasta with a nice extra-virgin olive oil. Everything gets mixed together before eating, but the combined effect of the pretty vegetables and egg on top plus the intoxicating sesame smell makes for a very enticing final presentation.

Finally, cartoon-ish slurping is a must when eating bibim guksu, so maybe save your nice white T-shirt for another day—or at least have a Tide pen handy.