Spicy Korean Cucumber Salad (Oi muchim)

Refreshing and nearly effortless, this spicy Korean cucumber salad (oi muchim) features crisp chopped cucumbers tossed in a flavorful sweet & spicy, salty & tart dressing. Take advantage of seasonal vegetables or make a dent in your own cucumber harvest and serve this with Korean or Asian-inspired soups & stews, grilled or braised meats & fish or toss it into a mixed rice or noodle dish.

What is spicy Korean cucumber salad/Oi Muchim?

In Korean, “Oi” means cucumber and “muchim” translates to something like “seasoned vegetables” or “vegetables mixed with seasonings.” Muchim are one type of a broader category of Korean side dishes called banchan. 

Banchan are small plates served before or alongside rice and a Korean main dish and include anything from kimchi to steamed and seasoned eggplant or simple seasoned spinach. 

Serve this spicy cucumber salad alongside rice and a simple Korean or Asian-inspired main, like soy braised chicken with ginger and garlic or Cantonese steamed fish.

Many banchan, like kimchis, are prepared well in advance and allowed to ferment so they will keep well over the fall and winter months. Others, like this cucumber salad, are meant to be eaten quickly after they are made and serve as a means of using fresh in-season summer vegetables, often harvested from the home garden. In traditional Korean households, muchim brought similar, if less complex, flavors of fermentation to the table at a time of year when the homemade kimchi may have run out. 

Typically, Oi muchim is served as one of many in an assortment of banchan (usually at least 3) on the Korean table, but it can also be served as a simple side salad or stand alone side dish for Korean soups, stews or braised or grilled meats, other Asian inspired meals or even as a summer side salad to a simple Western-style meal of meat and potatoes.

Choosing the right Cucumber Variety

While any cucumber can be used to make this salad, ideally you want to look for a long slender variety that is either seedless or contains very few, small, seeds. English hothouse cucumbers or kirby cucumbers, an especially crunchy small variety intended for pickling, are commonly used to make Korean cucumber salad. Any slender Korean, Persian or Japanese cucumber variety can also be used.

This salad is a staple side dish in my house around cucumber season when I’m drowning in cucumbers from the inevitably too many cucumber plants I’ve planted. My preferred varieties to grow in my kitchen garden are China Jade and Shintokiwa - both crisp, long and slender Asian varieties that perform well in my zone 5b North Eastern coastal garden.

What to do with Excess Liquid

Cucumbers are made primarily of water. Just how much water depends on the variety and size of the cucumbers you use. Smaller, younger cucumbers have less water content, so pick them when they’re on the smaller side if you’re harvesting them from your garden.

The longer you leave cucumber salad sitting, the more liquid will pool at the bottom of the bowl. This isn’t a big deal, and you can always serve the salad with a slotted spoon, but if you want to minimize the excess liquid in your salad you can: 

1. Scoop out the seeds and soft centers of each cucumber with a spoon after you have cut them in half and discard the seeds and soft insides. This is an especially helpful technique if all you have are large cucumbers with lots of seeds. 
2. Salt and drain the cucumbers after chopping: place them in a large colander or sieve set over a large bowl. Add salt and toss the cucumbers well to evenly distribute the salt. Leave them to sit and drain for 20-30 minutes (or longer, if you have time). Then, rinse the cucumbers with water to remove the extra salt and drain away the liquid.

If you’re in a hurry, you can skip either or both of these steps. It won’t matter as much if you intend to eat the salad right away, especially if you only make as much salad as you plan to consume in one meal. If you end up with a ton of liquid under your salad, be sure to toss again before serving and use the excess liquid to spoon over rice or noodles.

Make this Oi muchim ahead to have on hand for adding fresh vegetables to simple noodle or rice dishes like scallion oil noodles or crispy rice bowls.

Ingredient Substitutions

Gochugaru

Gochugaru is a key ingredient in this salad. Crushed or coarsely ground dried chilies with a texture that falls between chili flakes and chili powder, gochugaru have a vibrant appetizing red color and a unique flavor that’s slightly sweet, fruity and a little bit smoky with a mild to medium heat level.

Gochugaru is widely used in Korean cuisine and can be found in anything from kimchis, gochujang, soups and stews, and banchan. 

Because of its ubiquity in Korean cooking, it is common in Korean households to make your own and you can too, if you grow the right peppers in your garden or if you have access to fresh or dried Korean chilis at a specialty Korean market. But you can also purchase gochugaru at a well-stocked grocery store, a local Asian market or order it online. 

If you can’t access gochugaru, you could just leave it out for a mild, non-spicy, version of the salad. If you’d like to make a substitution there are a few options: 1) Use a mix of cayenne and smoked paprika or chipotle powder. It won’t taste the same, and cayenne is spicier than gochugaru, but your salad will probably still be delicious. 2) Use a bit of gochujang, or red chili paste, if you have access to it. It has a similar spice level and some of the same flavor, but it also contains glutinous rice and soybeans, so it has a thick paste-like texture and a few additional flavor notes that aren’t present in gochugaru.

Italian red pepper flakes aren’t a great substitute for gochugaru. They are spicier, have a coarser texture, a different flavor profile and a slight bitterness when eaten raw.

Rice Vinegar

If you don’t have rice vinegar, you can substitute another mild-flavored vinegar such as apple cider or white wine without changing the overall flavor of the dish too much.

Sesame Oil

Sesame oil gives this salad a distinct nutty flavor, if you omit it the salad won’t taste the same but you can substitute a neutral-flavored oil like canola or vegetable. If you still want that sesame flavor without the sesame oil, add extra sesame seeds and toast them in a dry pan for a few minutes before adding to the salad.

Fish sauce 

The main purpose of the fish sauce in this salad is to add saltiness and a rich umami flavor. Fish sauce has become easier to locate at any well-stocked grocery store, but if you can’t find it you can substitute soy sauce which will give you the saltiness, but won’t impart the same fermented funky umami flavor.

Want more easy vegetable-centric sides ready in less than 30 minutes? Try these sautéed  collard greens or these honey sriracha brussels sprouts. 

What to serve with Korean Cucumber Salad

Spicy Korean cucumber salad is extremely versatile and can be served with nearly anything but goes particularly well with:

• Rich or meat-heavy dishes like slow braised meats and stews.
• Summer barbecue foods like chicken wings, tacos and grilled meats and vegetables.
• Simple mixed rice bowls topped with a fried egg, or mixed in with your morning eggs.
• Any main and carb combo that features Korean or other Asian-inspired flavors.

Notes on Making Spicy Korean Cucumber Salad

• Like most traditional dishes, Korean banchan recipes vary from region to region and sometimes from household to household. Don’t worry about getting it exactly how it “should” be. Spicy korean cucumber salad is such a simple recipe that it really is all about balancing the flavors - to your taste. After making the salad, taste and adjust the seasonings according to what you like. 

• Relatively speaking, Oi muchim is mildly spicy. But if you are worried about the spice level, prepare the marinade with ½ the gochugaru, mix with the cucumbers, taste and add the rest of the gochugaru only if you’d like it to be spicier.
• Always toss the cucumbers through the dressing again just before serving to ensure all of the cucumber is coated with any liquid and seasonings that may have sunk to the bottom of the bowl.
• This salad can be served either at room temperature or cold. If you make it ahead and refrigerate it, know that it will release liquid as it sits - even if you salt the cucumbers before assembling. Store leftover salad for up to 3 days in an airtight container in the refrigerator.