🟢 Great-in-Tokyo — Great experience you can enjoy in Tokyo.
Overflow “Kobore Sushi” & Izakaya Feast at Isomaru Suisan in Togoshi-Ginza — From gunkan rolls piled high with ikura and sea grapes to rare "Island Sushi" and crispy tempura. Experience the lively atmosphere of a casual Japanese seafood banquet.
Last updated: 2025-12-31
Introduction
“Kobore sushi,” or overflow sushi, refers to gunkan-maki topped so generously that the ingredients spill over the sides of the rice and seaweed.
Rather than having a single birthplace, it is a style that has evolved across Japan as sushi shops created their own photogenic showpiece.
The example here comes from Isomaru Suisan in Togoshi-Ginza. Their version combines popping salmon roe and fresh sea grapes, making it a colorful plate.
What to Try
Kobore Sushi (Overflow Sushi)
"Kobore sushi" is not only photogenic but also a luxurious dish where the toppings far outweigh the rice. Enjoy the generous assortment style that varies by restaurant.
Shima Sushi (Island Sushi)
This is a local specialty of the Ogasawara Islands in Tokyo. Fish marinated in soy sauce (known as "Zuke") is used as the sushi topping. The soy sauce soaks into the fish, offering a flavor different from standard sashimi.
💡 Did You Know?
Tokyo is the "Longest" Prefecture in Japan!
When people think of Tokyo, they imagine a crowded concrete jungle. But surprisingly, Tokyo extends over 1,000 km south to the Ogasawara Islands (and even further to Okinotorishima), making it the "longest" prefecture from north to south.
Because of this vast ocean territory, Tokyo actually has a thriving fishing industry. Fishermen in Ogasawara catch fresh Tuna, Wahoo, and Bonito—which are exactly the types of fish used for the Shima Sushi mentioned above!
Chikuwa Isobe-age
This is tempura of chikuwa (fish cake) fried with batter mixed with green laver (Aonori). It enhances both the appearance and the flavor. It is flavorful enough to eat without any dipping sauce. It is a standard item on Izakaya menus.
Fried Soft-Boiled Egg with Ikura & Oni-oroshi
A soft-boiled egg is made into tempura and served with dashi. It is then topped with coarsely grated daikon (Oni-oroshi) and Ikura (salmon roe). While close to creative cuisine, the finish is distinctly Japanese. Both the taste and appearance are guaranteed to be excellent.
Tokyo or Trip?
🟢 Great-in-Tokyo — Great experience you can enjoy in Tokyo.
Kobore sushi is a kind of “nationwide sushi culture,” evolving freely as restaurants around Japan add their own ideas.
If you spot it on the menu at a sushi izakaya, be sure to order it. You’ll likely encounter a plate that reflects that shop’s personality in a very direct, delicious way.
Explore Nearby
- Hamayaki in Tokyo — Isomaru Suisan’s Indoor Seafood Barbecue 🔥 (Same Restaurant!)
- Dashimaki Tamago in Togoshi-Ginza — The Japanese Art of Dashi-Rolled Omelet 🍳
- Kaki Fry in Togoshi-Ginza — Piping Hot, Crispy & Creamy 🦪
- Toyosu-Fresh Chutoro at a Hidden Izakaya in Togoshi-Ginza 🐟
- Togoshi-Ginza Guide 2026 — Walk Tokyo’s Longest Street for Authentic Local Eats 🏮
Similar Dishes
- Saba Sushi — Kyoto’s Traditional Marinated Mackerel Sushi 🍣
- Kanburi — Kanazawa’s Winter Yellowtail Sashimi 🐟
- Shiro-ebi Sashimi — Toyama’s Sweet White Shrimp 🐟
External Links
- Sea Grapes (Caulerpa lentillifera) — Wikipedia 🔗
- Ogasawara, Tokyo (Home of Shima Sushi) — Wikipedia 🔗
- Tokyo Local Food Guide (Includes Shima Sushi) — GO TOKYO 🔗
About "Taste of Japan"
Hello, I'm Yuta.
Born in landlocked Yamanashi and having lived in the gourmet city of Sendai for 10 years, I now call Togoshi-Ginza home. My frequent business trips across Japan allow me to constantly explore the diversity of regional flavors.
Why Togoshi-Ginza?
This street is Tokyo’s longest shopping arcade (about 1.3 km), but it holds a special history. It was the very first street in Japan to adopt the "Ginza" name—a tradition that later spread across the country—after receiving bricks from the famous Ginza district following the 1923 Great Kanto Earthquake.
My Wish as a Local
I am not a culinary expert. However, as a Japanese local who knows both the convenience of Tokyo and the origins of regional food, I want to share the "atmosphere" and "personal feelings" that you won't find in standard guidebooks.
The Concept: "Tokyo or Trip?"
Visiting every region of Japan in a single trip is nearly impossible. Some food experiences are worth the travel to the source, while others offer a fully satisfying experience right here in Tokyo.
This blog is a guide to help you make that choice. Based in Togoshi-Ginza, I share my honest experiences and "my personal answer" to help you maximize your culinary journey in Japan.
- 🟠 Local-First: Best experienced in its home region. Worth a trip.
- 🟢 Great-in-Tokyo: A nationwide favorite or regional specialty that offers a fully satisfying, authentic experience right here in Tokyo.
- 🟣 Tokyo-Do-Must: A unique food culture born in or exclusive to Tokyo.