Retrying cold bukkake udon with half-and-half katsu set: Kosi Seongsu

Ever eaten cold udon somewhere and been let down because it wasn't what you expected? I had that exact shock once at a restaurant supposedly famous for its bukkake udon — it just wasn't good.

This time I went to Kosi, a Seongsu restaurant known for cold udon and fresh pork loin katsu, and it completely erased that disappointment. Chewy, bouncy noodles, perfectly seasoned cool tsuyu broth for the bukkake udon, pork loin katsu, cheese katsu — if you're looking for properly made cold udon, I'd recommend Kosi.

What Kosi has in store

• Location of this Seongsu cold udon spot, 1 minute from Ttukseom Station
• Comparing the half-and-half katsu and the sets
• How Kosi's udon differed from the bukkake udon that once disappointed me
• Wrap-up: hearty katsu with pork loin and cheese

Location and parking, 1 minute from Ttukseom Station

Kosi Seongsu Branch is 1 minute from Ttukseom Station Exit 6 and 5 minutes from Seoul Forest Station Exit 1. Up to two cars can park in front of the restaurant free for one hour, and there's also public parking nearby at Seongsu Culture & Welfare Center or Seongdong District Sports Center.

It's right in the middle of the Seongsu-dong café street, Ttukseom Resort and Seoul Forest, so it'd make a great date spot too if you're already out in the area.

Half-and-half katsu and sets — how to order

If you're torn between just udon or udon with tonkatsu, I'd recommend ordering the set.

My friend added ₩5,000 to the cold udon for a set that came with tonkatsu, while I ordered the half pork loin, half cheese katsu set with mini udon added. Ordering different things meant we could share and try both flavors, which was great.

Eating udon and katsu together meant I could cleanse my palate with the cool udon while also enjoying crispy katsu — it made for a hearty, satisfying meal. The portions were really generous!!

What was different about the bukkake udon that once disappointed me

Since this place is known for its Seongsu cold udon, I had high expectations for the noodles. I was a little worried because of my earlier disappointment at another restaurant famous for bukkake udon, but the bukkake udon (chilled udon topped with cold seasoned tsuyu) at Kosi was clearly different.

The noodles were chewy and springy, with real bounce in every bite, and the cool tsuyu was seasoned just right, pairing perfectly with the noodles.

📍TIP: I heard the name Kosi itself is a Japanese word meaning "chewy texture," and after eating it, I could totally understand why they picked that name — the noodle texture was that distinct.

Apparently the fresh noodles are made in the 800-year-old Sanuki style and aged for 48 hours, and you could taste how much care went into the noodles. You could tell from every bite that each ingredient was handled with attention.

Wrap-up: hearty pork loin and cheese katsu

The pork loin tonkatsu wasn't tough at all — soft and moist, with juices coming through in every bite — and the cheese tonkatsu was packed with so much cheese it started oozing out the moment it was cut, moist and really delicious. In short, Kosi Seongsu Branch proved itself as a solid Seongsu, Ttukseom Station spot with both chewy cold udon and tender fresh pork loin katsu.

It's the kind of trustworthy place that'll naturally come to mind next time I'm in Seongsu-dong. This time I came with a friend, but next time I'm bringing my boyfriend.

Especially recommended for

• ✅ Anyone who's been disappointed by cold udon before
• ✅ Anyone looking for a meal while out in Seongsu-dong or Seoul Forest
• ✅ Anyone wanting a hearty meal with family, friends, or a partner

If you want to enjoy properly made cold udon and fresh pork loin katsu in Seongsu-dong, be sure to visit Kosi Seongsu Branch. Which do you prefer when eating udon — hot or cold?