Gwangjin katsu restaurant with hot udon sets: Kosi

After my husband and I had our first wedding-anniversary date, we were about to head home for dinner—but since we were in Seongsu for the first time in ages, we went to Kosi Konkuk University Branch! A teacher I worked with brought me here the first time because she said it was good, and I got hooked then; I’ve probably been back around 10 times, a true regular spot. The tonkatsu is always on point and the cold udon is delicious too, so I’d come here with my husband a few times as well~

There can be a bit of a wait at weekday lunchtime, but I visited after our weekend date, so thankfully we walked straight in with no wait 👍🏻

Inside Kosi Konkuk University Branch and the seating

There are lots of tables, and the restaurant is quite spacious! Most are four-person tables, with a few two-person tables and bar seats in between, so it’s also great for eating alone. I came by myself for lunch plenty of times after weekend shifts too 👤

Each table has a kiosk, so you can order comfortably from your seat. I also loved that you can pay right there too—no need to make a separate trip to the counter!

Tonkatsu and udon menu

• Cold udon: bukkake udon, single ₩9,000 / set ₩13,000; ten bukkake udon, single ₩10,500 / set ₩14,500
• Tonkatsu: tonkatsu, single ₩11,500 / set ₩15,000; assorted katsu, single ₩14,500 / set ₩18,000
• Hot udon: kake udon, single ₩9,000 / set ₩13,000; tori-ten udon and katsune udon, single ₩10,500 / set ₩14,500
• Donburi (rice bowls): gyudon, ebidon, and karaage-don, ₩10,000 each

Udon sets come with tempura, while katsu sets come with kake udon! My husband chose the ten bukkake udon set, topped with shrimp and kabocha squash tempura, while I wanted hot udon too, so I finished ordering the assorted katsu set 🪄 Plus a Fanta~

Ten bukkake udon set and assorted katsu set

What a generous spread! Since we both ordered sets, there was so much food 🌟

My husband’s ten bukkake udon set

The added tempura with the set included sweet potato, shrimp, kabocha squash, and perilla leaf, plus one piece of yubu chobap (fried tofu sushi) 🍤 Since it’s bukkake udon, you pour on the separately served broth to your liking. The udon noodles were seriously so chewy, with a great bite 🤤

I love sweet potato tempura, so I dipped it right into the sauce for a bite! So crispy and tasty, yum yum.

Assorted katsu set with hot udon

I wanted both cheese katsu and tonkatsu, so I ordered the assorted katsu—and yep, I’m so glad I did 🤤 Maybe because the weather was starting to cool down, I was craving hot udon too, and its noodles were wonderfully chewy as well!

Tonkatsu and cheese katsu you can always count on! I ate the tonkatsu first and had the cheese katsu afterward, so this was taken a while after it came out, but the cheese was still stretching like crazy. So fascinating~

There are even vitamins by the counter as you leave after eating, perfect for a little palate refresher on the way out 😊

A beloved regular spot that was lovely to revisit

Kosi was just as delicious as I remembered, even after a long time! I used to come here often when I was at my old job, so it felt even nicer to return on my wedding anniversary, haha. From the tonkatsu and cheese katsu to the udon, everything was delicious without a weak link, and the staff were all so kind that it made for such a feel-good meal~ If you’re looking for great tonkatsu or udon around Seongsu or Konkuk University Station, everyone, go Kosi 😃