Udon restaurant with a solo dining zone in Gwanak, Seoul: Kosi

This is the place my sister — a regular at a Hongdae udon shop — took one bite of and raved about: Kosi, a well-known spot near Seoul National University Entrance Station. We went around 1:30pm on a Monday, deliberately timing it to avoid the break time (3pm to 5pm) so we could eat at ease, but the tables were nearly full anyway. We came for a nice meal together, but this place is also famous among local office workers as a reliable lunch spot, so the foot traffic never really stops.

Where Kosi is in Gwanak, and its opening hours

• Address: 466 Bongcheon-ro, 101ho, Gwanak-gu, Seoul, South Korea (2-min walk from Exit 5, Seoul National University Entrance Station)
• Hours: Daily 11:00 - 20:50
• Break time: 15:00 - 17:00
• Amenities: Takeout, delivery, Wi-Fi, waiting area, reservations, group seating available

How to walk to Kosi from Seoul National University Entrance Station, and how long you'll wait

It's an easy walk — just 1 to 2 minutes from Exit 5, so public transit access is great. It's close enough to the main road that you won't get lost even on your first visit.

Right at the entrance there's a waitlist sign-up sheet, with a menu posted right next to it. It's a nice touch that lets you pick your order while you wait outside.

As for parking, it's generally not available, though I heard weekends and holidays can be more flexible depending on the situation. But transit here is so convenient, and this is exactly the kind of place you want a cold beer with, so I'd recommend leaving the car at home.

Inside Kosi: solo dining zone and tables for 10

Walking in, the high ceilings and ivory-toned walls give the space an open, bright, cozy feel. It's kept very clean and comfortable overall, the kind of place where families with kids can eat without worry.

There's a solo dining zone with 4 seats along each side wall, great for eating without worrying about who's around. When I visited, more than half of the solo tables were taken — there are a lot of solo diners here. In the center and further back there are four 4-tops and two 2-tops spaced comfortably, and if you line up one wall's 4-top, 4-top, and 2-top, you can seat a group of 10.

I especially liked that each table has a tablet PC for ordering and payment — super convenient — and it was fun to sit and peek at the busy cooks through the clean open kitchen.

What we ordered at Kosi and what it cost

We ordered the ten bukkake udon set (₩16,000), the tonkatsu set (₩15,000), and — an essential to this perfect combo — a bottled Asahi (₩6,000).

Cooking started the moment we ordered, and soon a generous, neatly plated spread arrived at our table. Udon and tonkatsu are common enough dishes, but there was a sign in the restaurant saying they use directly sourced ingredients, and once I saw the plating, that pride made sense. In particular, the kake udon that came as a side with the tonkatsu set was so generous I thought they'd accidentally given us a full main — great value.

How the sanuki udon noodles and freshly fried tonkatsu tasted

The first thing that caught my eye was, hands down, the pale, glossy udon noodles. True to the description that they're made using traditional Japanese sanuki methods, the coiled noodles in the bowl looked wonderfully plump and springy. I'd heard this place got famous after appearing on SBS's Master in the House, and seeing those bouncy noodles in front of me, I got it instantly. The tonkatsu that came alongside was just as impressive — the batter had no soggy spots and stayed crisp like a blooming flower, seriously appetite-stirring.

Even the salad and side dishes included with the set were neatly arranged, clearly set up to let the mains shine.

Ten bukkake udon set, 16,000 won

Ten bukkake udon is a cold-style udon where you mix in a generously poured, chilled tsuyu (dipping/pouring sauce). The house-made tsuyu, simmered from soy sauce sourced from Japan, wasn't overly salty and had a wonderfully subtle umami depth.

As the cold tsuyu hit the noodles, the already-chewy sanuki udon tightened up even more, giving a satisfying bounce with every bite. Wow — this chewy texture that cold udon delivers is a completely different charm from the warm, brothy kind.

A clean broth base made from southern-coast anchovies and kelp lifted the tsuyu's depth even further, and the base was so good that my sister forgot to even add the radish, scallions, or tempura crumbs, and just inhaled it. It was only after she finished, looking at the empty bowl, that she realized she'd skipped the toppings. It was perfect even without them, but she said she was already looking forward to trying it with the toppings next time.

Tonkatsu set, 15,000 won, with kake udon on the side

Even the side kake udon that came with the tonkatsu set had firm, chewy noodles. The broth was clean and deep in flavor, the kind that gently warms you from the inside.

True to the sign noting a 24-hour aging process, the moment you bite into the tonkatsu, crispness gives way to juicy, tender meat that fills your mouth. What especially stood out was how the batter and the meat never separated when chewed — they stuck together perfectly, which really shows off the chef's frying skill.

A light sprinkle of pink salt brings out the pork's savory flavor even more strongly, and the seasoning on the meat is so on point that salt alone makes it a fantastic dish. My own little tip is to mix the wasabi that comes with the meal into the tonkatsu sauce and dip generously — the wasabi's kick cuts perfectly through the sweetness of the sauce and neutralizes the tonkatsu's richness.

Pairing all this with a crisp, refreshing Asahi brought the savory fried notes and the udon's umami into perfect balance.

Thanks to the care put into every single ingredient, we left with a really satisfying, filling meal. Next time, I'm making sure I'm the one who gets to try that ten bukkake udon my sister loved so much she forgot the toppings.