Come summer, gazpacho recipes are about as predictable as the heat that inspires them. I don't mean to sound dissatisfied, because I love gazpacho as much as anyone—who wouldn't want a refreshing chilled soup made from some of the best ingredients of the season? But this summer, I've been sustained by an entirely different cold soup, and now I want to share it with you.
I'd like to introduce you to mul naengmyun, a Korean soup made from a sweet-tart, icy-cold broth, chewy buckwheat noodles, and refreshing toppings like cucumber, pickled radish, and Asian pear. I eat at Korean restaurants several times a month, and this dish has been my repeat choice throughout the summer. So, with guests coming over for dinner the other weekend, and with uncomfortably high temperatures predicted, I decided I'd try my hand at cooking a version of it at home.
Rule #1 of dinner parties: never cook a dish for the first time.
I really have to thank my dinner guests for this recipe though, because they suffered through my first botched attempt—the chilled soup that sat, refusing to melt, like blocks of Jell-O in their bowl. I still don't know how they managed to choke it down, but it was a necessary failure that led me to a recipe that works.
The Stock: What Went Wrong and How I Fixed It
In short, I was foiled by my own cooking orthodoxy. One of the rules I generally live by is that a good stock should be simmered slowly to extract as much gelatin as possible from bones and meat scraps: when chilled, it should set into a firm gel. It's one of the secrets to creating soups and sauces that are rich and full-bodied even before any butter or other fat is whisked in.
I figured this large load of gelatin would be a good thing for a chilled soup. Because gelatin inhibits ice-crystal formation while acting as a stabilizer to slow down melting (which is why it's sometimes added to ice-cream bases as well), I figured it would help my broth freeze less hard, and would slow its melting to prolong the slushy experience—perfect for a soup that should be served partially frozen with a slightly slushy texture*.
*Some folks just serve the broth chilled and drop ice cubes into it, but the idea of water melting into and diluting the broth didn't appeal to me, so I went with the slightly trickier soup-slush version.
In my first pass at the broth—the version I served to my hapless guests—I went for maximum gelatin, loading my stockpot with connective tissue-rich ingredients like chicken feet and a cow's foot. But I forgot one little detail: I was making a cold soup, not a hot one. Too much gelatin wasn't just going to slow the melting point and prolong the slushy experience, it was going to prevent it from melting altogether. Even at room temperature, I had a solid mass on my hands. Instead of serving my guests an icy soup, I was forced to serve them a quivering bowl of meat jelly.
After that, I realized that I to scale back my ambitions to make a simpler broth—one with a milder amount of gelatin in it. At its easiest, the broth I came up with is just store-bought chicken broth enhanced with fresh ginger, scallions, garlic, and a small amount of unflavored gelatin. Even better, though, is if you use homemade chicken stock, in which case a quick infusion from the aromatics and no extra gelatin (since homemade stock should already have at least a little) is all that's needed.
When researching this recipe, I found many examples that called for a one to one blend of chicken and beef broth. Unfortunately, it's not practical for everyone to get beef bones, and most store-bought beef broth is not very good. So I decided to infuse the chicken broth with a little beef flavor by quickly poaching thinly sliced beef brisket in it. The cooked brisket is frequently served in mul naengmyun anyway, so why not get its flavor into the broth?
One other important lesson I learned about homemade broth: it's important to skim it completely of all of its fat (you can do this by removing the fat disk after the broth has chilled). Cold animal fat leaves an unpleasant waxy texture in the finished dish.
Before freezing the finished broth, the final step was to add some pickling liquid from Korean pickled radish, which is both sweet and vinegary. I went to a Korean supermarket and found the pickled radish product below, but if you can't find it, don't worry: you can add a splash of rice vinegar and a touch of sugar to the broth instead for a similar flavor. Either way, go easy on it, since the soup is served with vinegar on the side for diners to add according to their tastes.
I don't speak Korean, but if I understand correctly the "naengmyun" in mul naengmyun refers to the cold noodles typically served in this soup. Often made at least in part from buckwheat, they're incredibly quick-cooking and have a slippery, chewy texture.
The package I bought had the noodles conveniently separated into portion sizes, which made things very easy.
As soon as they're cooked, which only took a minute or two, I ran them under cold water until thoroughly chilled to prevent them from overcooking and to rinse off any excess starch that could cause them to stick together. I pressed out the excess water before setting the noodles into bowls.
With the stock set and the noodles cooked, I arranged fresh toppings on the soup to serve.
I went with the things I've seen it served with it restaurants: silvers of cucumber and pickled radish, along with Asian pear (pictured here), hard-boiled egg, and those brisket slices.
At the table, pass around some mustard or mustard oil as well as some vinegar. Diners can add each to make the soup as piquant and tangy as they like.
Am I saying that mui naengmyun is going to outright replace your gazpacho as the summer soup of choice? No. But it's gonna try its hardest to give that gazpacho a run for its money.