Yayoi Brand Guidelines: Plenus’s Japanese Set-Meal Chain, Run in Thailand by MK Since 2006

A Japanese set-meal chain from Plenus.

Yayoi is a Japanese set-meal brand that reached Thailand under licence. In Japan the chain trades as Yayoiken and belongs to Plenus, the company also behind the Hotto Motto takeaway-lunch chain. Plenus’s own history says it opened its first Meshiya-don set-meal restaurant in Fukuoka in December 1989 and renamed that chain Yayoiken in July 2006; Japanese Wikipedia dates the first restaurant under the Yayoiken name to September 2004, before the wider renaming. Plenus says the chain passed 200 restaurants in July 2012 and 300 in March 2016.

Plenus is a postwar business. Its own account traces it to a business-machines company founded in 1960 by Sueyuki Shioi; Japanese Wikipedia dates the company to 1976 in Sasebo, Nagasaki, under the name Taiyo Jimuki. Both sources agree that it entered food in 1980 as a regional franchisee of the Hokka Hokka Tei lunchbox chain in Kyushu, and that it took the name Plenus in December 1990. Japanese Wikipedia says the name comes from a Latin word meaning full or complete.

The company has since changed shape. It registered its shares for over-the-counter trading in July 1993 and joined the first section of the Tokyo Stock Exchange in December 2002, according to its own history, and it left the exchange in February 2023 after a management buyout by the founding family’s holding company, which Japanese Wikipedia describes. Plenus moved to a single head office in Ginza, Tokyo, in January 2023.

The link with MK is older than Yayoi’s Thai restaurants. Plenus set up a subsidiary, Plenus MK, in December 1993 to run MK sukiyaki restaurants in Japan, and folded it into the parent company in June 2022, according to Plenus’s own history. The Bangkok Post reported in July 2013 that MK had grown its sukiyaki chain abroad through Plenus, which it described as the owner of the Yayoi brand in Japan.

MK’s Japanese chain.

In Thailand the brand is simply Yayoi, and it is run by MK Restaurant Group. The Thai Yayoi website says the first Thai branch opened on 1 March 2006, and Thai Wikipedia gives the same year and describes the arrangement as a franchise granted by Plenus. In April 2017 the Bangkok Post reported that MK had received rights from the Japanese company to expand Yayoi in Thailand and Singapore for 11 years, and that Thailand had been Yayoi’s first international market, ahead of Singapore, Taiwan and the United States. The paper also called Thailand the brand’s biggest market outside Japan.

The network grew in steps that the press recorded. As of 31 March 2013 MK ran 95 Yayoi restaurants in Thailand, the Bangkok Post reported that July; by the end of 2014 the count was 130, the paper reported in March 2015. Thai Wikipedia gives 191 branches at the end of 2021, the Thai Yayoi website said in October 2023 that there were more than 200, and English Wikipedia counts 193 as of 31 December 2024.

Yayoi also sits inside MK’s own buildings. When MK opened London Street, a food mall on Phatthanakan Road in Bangkok, in March 2015, Yayoi was one of five group brands under its roof, alongside MK Suki, Miyazaki teppanyaki, the Le Siam Thai restaurant and the Le Petit café, the Bangkok Post reported. The Thai website shares the group’s MKONE member card with MK.

The food is organised as sets. Thai Wikipedia lists single dishes and set meals including pork cutlet with miso sauce, grilled pork on a hot plate, beef rice bowls and Japanese bento, with udon, ramen, gyoza and desserts. The Thai website in 2026 sorts its menu into snacks, sets, donburi, bento, noodles, side dishes, drinks and desserts, adds nabe hotpots such as a miso-tomato nabe, and offers catering and large group orders for meetings.

Thai restaurant chains.

Thailand’s restaurant, bakery and café chains tend to present themselves through the places where people meet them: shopping centres, hypermarkets, community malls and their own stand-alone sites. Thai Wikipedia says most MK Suki branches sit in shopping centres and community malls, and in 2015 the Bangkok Post described MK Restaurant Group opening a food mall of its own in Bangkok, London Street, with five of its brands under one roof.

Menus are published by named dishes and drinks rather than by abstract promises. Chains sort their websites into sets, single dishes, desserts and drinks, run seasonal promotions around one dish or sauce, and tie repeat visits to member cards; MK and Yayoi, for example, share the MKONE card. Shopfronts, mascots and packaging are described brand by brand in each guide, as far as dated sources and the companies’ own pages show them.

Ownership is often layered. Several chains in this series sit inside larger groups, among them MK Restaurant Group, PTT OR, the CP group and Food Passion, and some international brands reach Thailand under licence: Yayoi, a Japanese set-meal chain, is run in Thailand by MK Restaurant Group under rights from the Japanese company Plenus, the Bangkok Post reported in 2017. Thai chains also go abroad through franchisees and joint ventures, as MK did in Japan, Vietnam and Singapore.

Corporate pages usually tell a founder story, a list of milestone branches and a record of franchise partners, and listed companies add filings with the Stock Exchange of Thailand. This guide separates what independent, dated sources record (founding dates, owners, listings, branch counts as of a stated date) from what rests only on a company’s own pages, and attributes the latter plainly.

One tray, one licence, two companies.

The Thai website explains the set-meal idea in plain terms: steamed rice, miso soup, a main dish and side dishes served together on one tray, which it calls the distinctive feature of the meal. It writes the name in Thai script and in Latin letters, and the Thai name drops the “-ken” of Yayoiken, the name Plenus uses for its own restaurants in Japan.

Singapore followed. In July 2013 the Bangkok Post reported four Yayoi restaurants in Singapore as of the end of March that year, and Plenus’s own history dates a Singapore joint venture with MK, Plenus & MK, to February 2011. Plenus’s history also lists its own overseas companies in Australia from March 2013, in Taiwan from January 2014 and in the United States from February 2014, separate from MK’s Thai network.

In Thailand the brand is one of several Japanese restaurant formats inside MK Restaurant Group. The Bangkok Post reported in March 2015 that the group also ran Miyazaki, a teppanyaki chain, and English Wikipedia lists 15 Miyazaki restaurants and two Hakata ramen restaurants at the end of 2024.

For a design guide, Yayoi shows how a licensed name can keep one format, the set meal on a tray, while a local group builds the network and the membership around it. Compare MK Restaurants, the sukiyaki chain of the group that runs Yayoi in Thailand, and S&P, the Bangkok bakery-restaurant chain covered in this series. For this guide we use a miso brown, a lacquer black and a vermilion with a serif, an unofficial interpretation; no product or logo is reproduced.

Keep Yayoi’s identity on hand — save it to a board in the Made Good inspiration library.