# Solo lunch set with tonkatsu near Ttukseom Station: Kosi Seongsu - By Sodam (https://superchart.com/en/@napkin-table-seoul/) - Written Sep 8, 2026 - Local places › Restaurants › Seongdong, Seoul - Sponsored: This post was written as part of a paid restaurant-visit sponsorship. - English edition: https://superchart.com/en/@napkin-table-seoul/seongsu-bukkake-udon-solo-lunch/ - Also in: [한국어](https://superchart.com/ko/@napkin-table-seoul/seongsu-bukkake-udon-solo-lunch/index.md) ## In short Kosi Seongsu Branch is a Japanese udon and tonkatsu restaurant in Seongsu, Seoul, a 5-minute walk from Ttukseom Station Exit 6. Ordering the bukkake udon set with a ₩5,000 tonkatsu add-on on a weekend afternoon, the noodles were chewy and the sauce wasn't too salty, making it taste even better than the writer's earlier visit to the Gyodae branch. With both solo tables and group seating, it's a solid pick for a solo weekday lunch if you work in Seongsu. ## Good to know - **Hours**: Daily 11:00–21:00 (break time 15:00–17:00, last order 20:30) - **How to visit**: Walk-in waitlist, sign-up sheet on-site - **Location**: 5-minute walk from Ttukseom Station Exit 6 - **Parking**: No dedicated parking; public transit recommended - **Seating**: Solo tables available, group seating available - **Other**: Groups welcome, takeout/delivery available - **Tonkatsu add-on**: ₩5,000 extra with the set menu *as written by the visitor on Sep 8, 2026* Trying to figure out what to eat for weekend lunch, I got a craving for cold udon and went searching — and that's how I found this place. 🍜 I'd actually been to the Kosi branch near Gyodae before, but when I heard a new one opened in Seongsu, I ran straight over! If you work in Seongsu and are craving Japanese food like udon or tonkatsu for lunch, this one's for you ✨ ## Kosi Seongsu Branch hours and visiting tips ⏰ Hours: Daily 11:00–21:00 (break time 15:00–17:00 / last order 20:30) 💡 How to visit: Walk-in waitlist (sign-up sheet) ⚡️ Other: Groups welcome, takeout/delivery available - The bukkake udon noodles were so chewy that the Seongsu branch felt way tastier than the Gyodae branch - It's basically an unwritten rule to order the set and add tonkatsu — just get the set, no question - It's only a 5-minute walk from Ttukseom Station Exit 6, so public transit is way more convenient ## Getting to Kosi Seongsu Branch from Ttukseom Station ![Exterior of Kosi Seongsu Branch, a 5-minute walk from Ttukseom Station](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-01-51z8f-900.webp) It's a 5-minute walk from Ttukseom Station Exit 6, so the access is really good. The walk over wasn't confusing at all, so it was easy to find. There's no dedicated parking, so I'd recommend coming by public transit. ![The area around the entrance of Kosi Seongsu Branch](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-02-1moa4-m-900.webp) ![The sign-up sheet area for walk-in waiting in front of the restaurant](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-03-1uwzh-900.webp) ### How long was the wait on a weekend lunch? There's no separate waiting area — you just write your name on the sheet out front and wait! On the weekend we visited, the place was completely full by around 1pm. Apparently there's a wait during weekday lunch hours too, so keep that in mind. ![The clean-looking interior of Kosi Seongsu Branch on first impression](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-04-17drq-900.webp) The moment I opened the door and walked in, my first impression was pure cleanliness 📸 ![The spacious dining hall and tables inside the restaurant](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-05-fmldy-900.webp) ![Solo tables and group seating available for dining alone or in groups](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-06-z8jjp-900.webp) ### Seating for both solo diners and groups The restaurant was way bigger than I expected, and there were separate solo tables, so eating alone didn't feel awkward at all. There's group seating too, so it works fine even if you come with a bunch of people. ## Menu at Kosi Seongsu Branch ![The menu board at Kosi Seongsu Branch](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-07-12us7-900.webp) ![A menu page listing the tonkatsu set](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-08-obkf9-900.webp) ![A menu page listing the udon dishes](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-09-kdeht-900.webp) ![A menu page explaining the set composition and add-on options](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-10-mk7t7-900.webp) ![A menu information board at Kosi Seongsu Branch](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-11-37wzc-900.webp) I heard the signature dish at Kosi, a tonkatsu spot near Ttukseom Station, is the tonkatsu set. We were really there for cold udon in the first place, so we ordered the bukkake udon — but since the set menu had a tonkatsu add-on option, I quickly added it on. ![The order: bukkake udon set with a tonkatsu add-on](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-12-1vo9k-900.webp) Always go with the set!! Pick the set!! haha My choice was a total win!! ### The basic table setting ![Sauce containers set on the table as the basic table setting](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-13-e42cy-900.webp) Once you sit down, there are sauce containers like this at the table — just use them to your taste. ## My review after eating the bukkake udon set ![A neatly served bukkake udon set on the table](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-14-1tqrs-900.webp) They served the set, and true to Japanese style, the presentation was neat and tidy. ![The bukkake sauce and toppings served separately](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-15-1siqh-900.webp) ![A dish of radish, scallion, and tempura bits toppings](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-16-1t9ks-900.webp) The bukkake sauce and toppings (radish, scallion, tempura bits) came separately, so you can add them to your own taste! Season the noodles however you like~ ![Bukkake udon with the sauce and toppings added in](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-17-ihudw-1200.webp) ![Chewy udon noodles lifted up with chopsticks](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-18-1lbpt-900.webp) The second I lifted a chopstick-full of noodles, I could instantly feel how chewy they were. The sauce wasn't too salty either, just right — I kept going back for more. ![A close-up of the bukkake udon mixed with seasoning](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-19-gu5bl-900.webp) ### How does it compare to the Kosi Gyodae branch? I've been to the Gyodae branch too, and personally, the Seongsu branch felt way tastier! The noodle texture and the sauce balance both felt like a step up. ![Tonkatsu with a crispy breaded coating](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-20-zqn1x-900.webp) ### The tonkatsu and inari sushi, added for ₩5,000 The tonkatsu was crispy outside and tender inside, and the udon-tonkatsu combo was seriously a perfect match. ![A piece of tonkatsu dipped in sesame-topped sauce](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-21-1j075-900.webp) Sprinkle some sesame seeds into the sauce haha, dip a piece of tonkatsu, take a bite~ This is the amount of tonkatsu you get for the ₩5,000 add-on with the set — pretty solid, right? ![A large-sized inari sushi](https://img.superchart.com/images/seongsu-bukkake-udon-solo-lunch/seongsu-bukkake-udon-solo-lunch-22-qtxeh-900.webp) The inari sushi (seasoned fried tofu pouch rice) was huge too — one piece alone left me feeling full. 💖 ## Final thoughts on Kosi Seongsu Branch I'd definitely recommend getting the set over a single dish! You get to enjoy the tonkatsu alongside it, which bumps up the satisfaction a lot. At this price, it felt like really good value for a weekday office lunch. If you work near Seongsu, I'd recommend stopping by during lunch hour. Especially if you love chewy noodles, this one's highly recommended! > Recommending Kosi Seongsu Branch as a solo-dining spot for Seongsu and Ttukseom Station office workers! ## Where it is - Kosi Seongsu Branch (코시 성수점) - 31 Sangwon 1-gil, Seongdong-gu, Seoul, South Korea - 서울특별시 성동구 상원1길 31 1층 - 37.5464155, 127.0474867 - Google Maps: https://www.google.com/maps/search/%EC%BD%94%EC%8B%9C%20%EC%84%B1%EC%88%98%EC%A0%90/@37.5464155,127.0474867,17z --- Superchart · https://superchart.com/en/@napkin-table-seoul/seongsu-bukkake-udon-solo-lunch/ · https://superchart.com/llms.txt