Summer Isn’t Complete Without These Quick and Easy Korean Cold Noodles

Cool down with a bowl of these Korean cold noodles, which get their spicy, sweet, and tart flavor from a gochujang-based sauce and extra nuttiness from crushed sesame seeds. Served with crunchy, juicy vegetables, a boiled egg, and a drizzle of sesame oil, it’s a hot-weather meal that’s light yet satisfying.

Overhead view of Bibim Guksu
Serious Eats / Matt Hunziker

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.

Overhead view of mixing noodles
Serious Eats / Matt Hunziker

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.

Overhead view of assembled bowls
Serious Eats / Matt Hunziker

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.

Overhead view of noodles
Serious Eats / Matt Hunziker

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.

Overhead of noodles in ice bath
Serious Eats / Matt Hunziker

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.

Overhead view of sauce ingredients
Serious Eats / Matt Hunziker

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.

Overhead of mixing noodles
Serious Eats / Matt Hunziker

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

Overhead view of assembly gif
Serious Eats / Matt Hunziker

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.

Overhead view of finished bowls
Serious Eats / Matt Hunziker

In a large bowl, set up an ice bath by partially filling it with a combination of cold water and ice. Set aside.

Overhead view of ice bowl
Serious Eats / Matt Hunziker

Bring a large saucepan of water to a boil over high heat. Using a spider or slotted spoon, gently lower eggs into water. Boil eggs for 8 to 10 minutes, then, using a spider or slotted spoon, transfer eggs to ice bath. Let eggs sit in ice bath until cool to the touch, about 2 minutes, before peeling under cool running water. Using a sharp knife, halve eggs; set aside. (Reserve ice bath for noodles.)

Overhead view of cutting boiled eggs
Serious Eats / Matt Hunziker

Bring same saucepan of water to a boil over high heat and add somyeon. Cook according to package directions, using tongs to constantly stir and move noodles around to prevent them from sticking to each other. Using a colander, strain noodles. Immediately transfer noodles to ice bath. Swish noodles around in the ice water to loosen them up a bit, then let noodles sit in ice bath while you prepare the sauce.

Four image collage of cooking noodles and swishing them in ice bath
Serious Eats / Matt Hunziker

In a large bowl, combine Asian pear, gochujang, rice vinegar, soy sauce, gochugaru, honey, toasted sesame oil, garlic, and water. Whisk until sauce is smooth. (Sauce should be fairly runny, which helps it to more evenly coat the noodles. You should have about 1 1/2 cups.)

Two image collage of mixing sauce
Serious Eats / Matt Hunziker

Drain noodles into a colander, then run the noodles under cold running water, vigorously agitating and scrubbing them with clean hands (as if you were hand-washing laundry), until they no longer feel sticky, about 30 seconds. Drain noodles well, then transfer to bowl with sauce. Using a clean and/or gloved hand, toss noodles with sauce to evenly coat. Season to taste, adding more vinegar, soy sauce, honey, or sesame oil as needed. (The sauce should taste equal parts spicy, tangy, sweet, and savory, with no one flavor overly dominating.)

Four image collage of rinsing and saucing noodles
Serious Eats / Matt Hunziker

Divide noodles amongst four shallow bowls. Top each bowl with some cucumber, perilla, and an egg half and drizzle with toasted sesame oil. Sprinkle the crushed toasted sesame seeds on top and serve. Have guests use chopsticks to mix the garnishes and noodles together before eating.

Overhead view of assembly gif
Serious Eats / Matt Hunziker

Special Equipment

Mortar and pestle, spider or slotted spoon, colander

Notes

There is no salt in this recipe, as many of the sauce ingredients are naturally quite salty.

Some Asian pears are less sweet than others. If yours is not particularly sweet, you may need to add more honey to achieve the right level of sweetness to temper the dish’s savory and spicy flavors. Asian pears can be expensive ($5 a pear when I last checked!), but grated Fuji or Gala apples make a very good substitute. You can also find inexpensive cans of crushed pear juice with pulp at  Korean supermarkets, which work well.

When buying gochujang, look for one that lists rice syrup instead of corn syrup in the ingredients list, as corn syrup can add an overpowering, cloyingly sweet flavor. When buying gochugaru, look for coarse flakes (akin to wheat bran), as opposed to the very finely ground flakes.

Although perilla leaves are part of the mint family, they have an earthy, anise-like flavor that is distinct from mint or other mint-y cousins such as shiso. You can substitute either for the perilla, but the effect will not be quite the same.

For convenience (or if you don’t care about aesthetics), you can add the sliced cucumber and perilla directly to the bowl of noodles and sauce and mix everything together, as opposed to serving the vegetables on top.

Although boiled eggs are common, you could add virtually any protein to this dish: poached chicken breast, cooked shrimp, baked tofu, thinly sliced ribbons of yuba. In his cookbook My Korea, the chef Hooni Kim tops his bibim guksu with shredded soy-braised and chilled brisket. It’s also a great vehicle for leftover grilled meats.

Make-Ahead and Storage

Bibim guksu sauce can be made up to two weeks ahead and refrigerated in an airtight container.