Buzz-worthy Beef Bowl Shop from Akasaka. Former Ad Agency Pro Opens 'GRAND MAISON GYUDON' in Omori for a Limited Time Starting May 1!
Koki Matsunaga, a former ad agency professional, is opening his refined beef bowl concept in Omori, Tokyo. Leveraging Mujaki Foods' 'Trust System,' the shop focuses on 'intra-oral cooking' to deliver a premium dining experience proven by previous long lines in Akasaka.
📋 Article Processing Timeline
- 📰 Published: April 28, 2026 at 01:25
- 🔍 Collected: April 27, 2026 at 17:01
- 🤖 AI Analyzed: April 28, 2026 at 00:28 (7h 26m after Collected)
■ Culinary logic derived from business thinking: A beef bowl without compromise
Koki Matsunaga, a former advertising agency employee, is set to open the beef bowl specialty store 'GRAND MAISON GYUDON.' Using the planning and proposal skills honed in the ad industry, he creates unique restaurant concepts and product development in the F&B sector.
'General beef bowl formats tend to focus on what to put on top. In my case, I emphasize the concept of "intra-oral cooking," where I design not only the flavor of the dish but also the specific way Japanese people eat. Against the standard soy sauce-based image, I shaped flavors that are "imaginable yet hard to replicate," such as miso-based ideas and a stamina-focused meat dish that younger generations would crave. As for Akasaka, I didn't actually open it for profit, but for analytical purposes. You'd think Akasaka would be expensive for rent and advertising, right? In reality, I started without any ads in a disadvantageous second-floor location of a snack bar in a back alley. I simply wanted to test if my product would sell. I started with only a few items I felt confident in, but it spread rapidly through word of mouth, naturally creating long lines.'
■ From success to setback, then to the final challenge
Mr. Matsunaga enjoyed a fulfilling life, gaining experience in advertising and restaurant management. However, in his 30s, he was diagnosed with depression and experienced significant losses, including his job and assets. Having gone through that period, he realized that if he could assemble the necessary pieces, he could succeed once again in a 'challenge for resurgence.' From there, he launched the Akasaka beef bowl specialty shop, gained confidence in his product, and is now opening 'GRAND MAISON GYUDON' in Omori by utilizing Mujaki Foods' Trust system.
'I have known about Tra-Navi (Trust-Navi) for a year and a half and was always curious. Since my original work was analysis and proposal, I gathered various information to see if I could really open a shop here. As a result, I wanted to try opening through this Trust system,' says Mr. Matsunaga.
Experience a luxury beef bowl with no 'filler items' this Golden Week
The store's motto is not 'eat once and done,' but a beef bowl shop you'll want to visit every day. Although the number of items is limited, each is a lineup without compromise, created by Mr. Matsunaga with an uncompromising attitude. For three days from the opening date of May 1st to May 3rd, 2026, the standard 1,580 yen Grand Beef Bowl can be enjoyed for 700 yen, and the 980 yen Golden Beef Bowl for 500 yen. Why not enjoy exquisite beef bowls with family and friends during Golden Week?
*As the number of daily preparations is limited, it will end as soon as it runs out.
■ Store Overview
Store Name: Beef Bowl Specialty Store 'GRAND MAISON GYUDON'
Address: 1F, 2-2-13 Sanno, Ota-ku, Tokyo 143-0023
Business Hours: 11:00–23:00
X: https://x.com/G_M_GYUDON
Instagram: @grandmaisongyudon
■ About Mujaki Foods Co., Ltd.
Established: March 1997
Representative: Representative Director and President Hayao Tashiro
Location: 17th Floor, Ebisu Garden Place Tower, 4-20-3 Ebisu, Shibuya-ku, Tokyo
Capital: 100 million yen
Business: Development and training of prosperous store owners, store expansion through outsourcing of prosperous store development, support and consulting for the Trust system.
Koki Matsunaga, a former advertising agency employee, is set to open the beef bowl specialty store 'GRAND MAISON GYUDON.' Using the planning and proposal skills honed in the ad industry, he creates unique restaurant concepts and product development in the F&B sector.
'General beef bowl formats tend to focus on what to put on top. In my case, I emphasize the concept of "intra-oral cooking," where I design not only the flavor of the dish but also the specific way Japanese people eat. Against the standard soy sauce-based image, I shaped flavors that are "imaginable yet hard to replicate," such as miso-based ideas and a stamina-focused meat dish that younger generations would crave. As for Akasaka, I didn't actually open it for profit, but for analytical purposes. You'd think Akasaka would be expensive for rent and advertising, right? In reality, I started without any ads in a disadvantageous second-floor location of a snack bar in a back alley. I simply wanted to test if my product would sell. I started with only a few items I felt confident in, but it spread rapidly through word of mouth, naturally creating long lines.'
■ From success to setback, then to the final challenge
Mr. Matsunaga enjoyed a fulfilling life, gaining experience in advertising and restaurant management. However, in his 30s, he was diagnosed with depression and experienced significant losses, including his job and assets. Having gone through that period, he realized that if he could assemble the necessary pieces, he could succeed once again in a 'challenge for resurgence.' From there, he launched the Akasaka beef bowl specialty shop, gained confidence in his product, and is now opening 'GRAND MAISON GYUDON' in Omori by utilizing Mujaki Foods' Trust system.
'I have known about Tra-Navi (Trust-Navi) for a year and a half and was always curious. Since my original work was analysis and proposal, I gathered various information to see if I could really open a shop here. As a result, I wanted to try opening through this Trust system,' says Mr. Matsunaga.
Experience a luxury beef bowl with no 'filler items' this Golden Week
The store's motto is not 'eat once and done,' but a beef bowl shop you'll want to visit every day. Although the number of items is limited, each is a lineup without compromise, created by Mr. Matsunaga with an uncompromising attitude. For three days from the opening date of May 1st to May 3rd, 2026, the standard 1,580 yen Grand Beef Bowl can be enjoyed for 700 yen, and the 980 yen Golden Beef Bowl for 500 yen. Why not enjoy exquisite beef bowls with family and friends during Golden Week?
*As the number of daily preparations is limited, it will end as soon as it runs out.
■ Store Overview
Store Name: Beef Bowl Specialty Store 'GRAND MAISON GYUDON'
Address: 1F, 2-2-13 Sanno, Ota-ku, Tokyo 143-0023
Business Hours: 11:00–23:00
X: https://x.com/G_M_GYUDON
Instagram: @grandmaisongyudon
■ About Mujaki Foods Co., Ltd.
Established: March 1997
Representative: Representative Director and President Hayao Tashiro
Location: 17th Floor, Ebisu Garden Place Tower, 4-20-3 Ebisu, Shibuya-ku, Tokyo
Capital: 100 million yen
Business: Development and training of prosperous store owners, store expansion through outsourcing of prosperous store development, support and consulting for the Trust system.