Fukuoka・Chicken Sukiyaki at Onioso in Yakuoji: The Warabimochi That Will Have You Coming Back for More!

I frequently visit the Yakuoji Onsen area for both work and pleasure, but my first encounter with Onioso (full name: Yakuoji no Yu Ryokan Onioso) actually happened through a business connection, rather than a trip with my dog, Elmo.

One day, while heading to Yakuoji for a meeting with a client, he suggested, “Since we’re here, let’s go have some of Koga’s famous Chicken Sukiyaki for lunch.” He took me deep into the mountains of Koga City, following a river until the view suddenly opened up to reveal a small, charming inn nestled in a traditional satoyama (rural mountain) landscape.

The moment we arrived, I was struck by the profound silence. “Wow, it’s so peaceful here,” I thought. I felt an immediate sense of calm. After talking with the Okami (proprietress) and doing some research later, I discovered that pets are welcome at the outdoor terrace seats. Ever since then, I’ve had it tucked away in my mind: “I have to bring Elmo here someday.”

Onioso: A Quiet Inn Tucked into the Yakuoji Mountains

Onioso is a small, traditional Japanese inn that retains a wonderful old-world atmosphere. Located at the very end of the Yakuoji Onsen district, the surroundings are incredibly quiet—it’s right in the heart of the countryside, with mountains behind and a river flowing below.

At the entrance, a wooden sign welcomes you. Inside, you’ll find classic ryokan features: red-carpeted hallways, polished wooden floors, and seasonal decorations like elegant Hina dolls or fresh flowers. It has a distinct “Showa-era retro” vibe, but instead of feeling old, it feels well-cared for and deeply relaxing. It’s the kind of place where you instinctively take a deep, slow breath.

The facility includes a dining area, hot springs, and a cafe space. Looking out from the lobby window, there’s a wooden deck terrace overlooking the satoyama scenery. The first time I saw it, I did a mental fist-pump: “Coffee out there would be absolutely incredible.”

The Main Event: Koga’s Specialty “Chicken Sukiyaki”

The primary reason my client brought me here was, of course, the Chicken Sukiyaki. A large pot was brought to the table, piled with fresh vegetables and glossy, high-quality chicken. The moment the sweet and savory aroma of the warishita (sukiyaki sauce) hit the air, my stomach went into full “foodie mode.”

Chicken Sukiyaki is essentially a poultry version of the classic beef dish, but unlike beef, it feels lighter, making it easy to keep eating. My client expertly added the chicken and vegetables to the pot, and once he gave the word—“It’s ready”—I dipped a piece into a bowl of raw beaten egg and took a bite.

…Total perfection.

The savory-sweet sauce brings out the rich umami of the chicken, all tied together by the mellow creaminess of the egg. I was genuinely moved; I had no idea Koga had such a hidden culinary gem.

Another interesting twist: instead of finishing the meal with rice, they use somen (thin wheat noodles). Tossing the noodles into the leftover sauce allows them to soak up every drop of chicken flavor. It’s dangerously delicious. Even though I was quite full by that point, I finished the noodles in no time.

The Real Star: The Addictive “Warabimochi”

While the Chicken Sukiyaki was fantastic, if you asked me, “If you go back to Onioso, what’s the one thing you’d eat?” I would answer Warabimochi without a second thought.

After the meal, we ordered this from the cafe menu. The price was very reasonable, making it an easy choice for a post-meal treat. What arrived was a plate of wobbly, translucent warabimochi (starchy jelly) dusted with roasted soybean powder (kinako) and drizzled with brown sugar syrup (kuromitsu).

It looked simple, but one bite changed everything. “Oh, this is the real deal,” I thought. It was soft yet had a satisfying chew, eventually melting away on the tongue. The fragrance of the kinako and the depth of the syrup were perfectly balanced. It’s the kind of treat where your chopsticks just don’t stop. Even though I was satisfied from the sukiyaki, the memory of this warabimochi lingered. Now, whenever I hear the name Onioso, I instantly think, “Man, I want that warabimochi again.”

From a Dog Owner’s Perspective: Terrace Seats & Walking Trails

Although Elmo stayed home this time, hearing that the outdoor terrace is pet-friendly was a game-changer. The wooden deck extends toward the mountainside with tables and chairs set up. I’m already imagining:

Enjoying a light lunch or rice ball set outdoors with Elmo.
Having a “cafe time” with warabimochi and coffee.

The area around Onioso is perfect for a stroll. There’s very little traffic, and the riverside paths and gentle slopes are ideal for a leisurely walk. My “dream plan” for a future visit looks like this:

Arrive in the Yakuoji area before noon.
Take Elmo for a walk along the river and through the countryside.
Have a light lunch or coffee/warabimochi on the Onioso terrace.
Let Elmo rest in the car for a bit while I soak in a private hot spring bath.
One last moment of zoning out on the terrace after the bath.

Just writing this makes me want to go right now! (laughs)

Next Time, It’s Warabimochi with Elmo

Reflecting on it, Yakuoji no Yu Onioso is:

A peaceful countryside inn nestled in the mountains of Koga City.
Home to the signature Chicken Sukiyaki, delicious right down to the finishing noodles.
A place for the Warabimochi, my #1 choice for a “must-eat-again” dessert.
Dog-friendly (terrace seats), making it easy to visit with your pet.
Surrounded by nature, perfect for a walk or a weekend drive.

Next time, I’ll be on that terrace with Elmo and a plate of warabimochi. Then, a relaxing soak in the hot springs, and a peek in the rearview mirror on the drive home to see Elmo fast asleep—that’s the perfect day I’m planning to make happen soon.

For more info and the latest hours, check the official site: Yakuoji no Yu Ryokan Onioso Official Website