Bonanza Coffee Roasters Mr. Kiduk Reus

Bonanza Coffee Roasters

Mr. Kiduk Reus

“I just want to show it through my actions.” A way of life; The founder achieved many things for the first time in a foreign country.

Inside specialty coffee shop Bonanza Coffee Roasters in Japan

Bonanza Coffee Roasters was founded in Berlin in 2006 as a coffee shop roasting coffee in-house and serving only coffee. Bonanza Coffee Roasters is planning to open their fourth branch soon and is also looking into expanding their business overseas. We interviewed the founder Mr. Kiduk Reus who has continued to take initiatives- unprecedented in Germany- focused on selling specialty coffee.

Logo and sign at specialty coffee shop Bonanza Coffee Roasters in Japan

“I thought about quitting many times.”

“When we started our business, we didn’t have a concrete business plan in mind. We just wanted to build a small coffee shop where our neighbors could come and we didn’t intend to do anything bigger than that. It’s not that we had any great ambitions or aspirations in mind because we were not even sure, first of all, if our business would be viable with such an unusual store style.” 

When Kiduk, who was born and grew up in South Korea, opened Bonanza Coffee Roasters in Berlin in 2006, nobody had heard of the third wave coffee. It was challenging and adventurous of him to start a coffee shop in a city where the coffee shop culture had not yet become widely known.

Serving customers at specialty coffee shop Bonanza Coffee Roasters in Japan

“You may think that things were going well when you think about how we do now, but I thought about quitting many times because the business was not going well. I had invested a lot of my own money, so I couldn’t simply quit. The most difficult time was around 2014 when we lost customers to other roasters such as THE BARN and Five Elephant.”

“Having said that, more and more people became interested in specialty coffee thanks to them, so the number of customers increased in the long run. In fact, our business at Bonanza Coffee Roasters took off starting to be just fine by the arrival of the third wave coffee trend.”

Brewing specialty coffee at Bonanza Coffee Roasters in Japan

 It all started with curiosity. 

Kiduk used to be a publishing designer at TBWA, an advertising company that was later established as a joint venture with Hakuhodo, a famous Japanese advertising company. Coffee for him was just a hobby that he enjoyed at home.  

Then his big curiosity in many different things took him to a new world for him. After quitting his job at the advertising company, he spent a year at home trying to learn how to make a good cup of espresso using a professional espresso machine, and soon after he accomplished that, he found himself in the professional realm. 

“As I kept trying and trying and thinking about how I could make the taste of coffee better, I started to wonder why people were drinking bad coffee. After discovering high-quality coffee from Monmouth Coffee given to me by a friend who lived in London, I began to think that making good coffee is not so difficult.”

“Perhaps it’s because when I am interested in a subject, I keep researching and looking for any possibilities to improve it until I am satisfied with the result. When I do that, I usually find a path, and others will also follow it.” 

Roasting specialty coffee at Bonanza Coffee Roasters in Japan

It’s no exaggeration to say that everything at Bonanza Coffee Roasters started with Kiduk’s curiosity. One example is that they develop and produce roasting machines that are easy to use.

“For example, we once developed a pressure gauge for a roasting machine in cooperation with a machine manufacturer. At first, those who had never used it said, ‘That’s impossible’ or ‘Why do you need to do that?’ However, it has become a standard device that is very important for improving the quality of roasting. Perhaps because we have the knowledge and expertise, we are often asked by world-famous companies to advise them on how to build or acquire equipment in recent years.”

Specialty coffee in Japan: Bonanza Coffee Roasters 01

The manufacturer at first said, ‘That’s impossible,’ but Bonanza Coffee Roasters was persistent and succeeded in commercializing it. This type of bag, which is highly airtight and protects against moisture and direct sunlight, has become an indispensable product for roasters.

“We believe that thinking of things that other people and companies don’t think of and continuously making small improvements is what creates our tag line of “unnecessarily good” value.”

Specialty coffee in Japan: Bonanza Coffee Roasters 02

People needed Bonanza Coffee Roasters.

The true value of Bonanza Coffee Roasters lies in the paradigm shift that they have created: integrating all of the elements into an innovative cafe design that only serves specialty coffee; roasting transparent green coffee beans harvested from specific farms in a way that makes the most of their profile; using a temperature-controlled espresso machine; measuring the amount of coffee beans for each cup of coffee; using a portafilter to provide latte art. 

Kiduk states, “The attitude of challenging new things with curiosity, thinking about how far we can go, how we can make things better, and how we can make things more interesting, has permeated our staff and is becoming a part of our corporate culture.”

The ability to break through with curiosity was also demonstrated in an emergency situation. Even during the lockdowns due to the Covid-19, people waited in line in front of Bonanza Coffee Roasters because they had devised a way to sell coffee through the shop window. 

Serving customers at specialty coffee shop Bonanza Coffee Roasters in Japan

“We knew that it would be a long battle against the virus, so we had to come up with a way to keep the shop open. As most of the coffee shops were closed, we were able to attract more customers than usual, and some customers were even saying, ‘It’s great that your store is open. I want to come here every day to drink coffee and support you financially.’ We can’t thank our customers enough for wanting to keep Bonanza Coffee Roasters open, and we are very grateful.”  

Behind the scenes during this time, there are efforts of the staff who tried to perform in the best interest of the company and not in their own interest. Since I heard other coffee shop owners lamenting that their staff had left them, I felt even more grateful for our staff who had placed their trust in the company.”

Specialty coffee in Japan: Bonanza Coffee Roasters 03

“I want to prove it’s possible.”

“It has been 15 years since I founded Bonanza Coffee Roasters. There were many hardships because I was only operating on my passions and I was often tormented by the thought that this was meaningless and that my life would never get better.”

“On the other hand, there have been a lot of fun moments, not so much because of having financial success, but because we get to work with people who find what we do interesting.”

“Now that we have worked with so many interesting people, opened so many new doors, and gained such a good reputation, many people have come up to us saying, ‘Your company is great.’ I think that even people in unknown cities in Egypt will know about the name of Bonanza Coffee Roasters in the future.”

“When I look back, I tried things anyway, even when I didn’t know what to do, which has led me to where I am today. When you have a curious mind, it can take you several steps ahead of ‘ordinary people.’”

“We are planning to open stores in other countries in the future, but this is also to show our staff that it’s possible to achieve what we aim for. If you do things the right way, you can make almost anything happen. I want to show that through my own actions.”

For Kiduk, running a business in a foreign country on his own was more difficult than he had imagined, yet he overcame many challenges and developed a strong belief that nothing is impossible in his dictionary. This may be the bonanza, or great achievement, of his life. 

Originally written in Japanese by Tatsuya Nakamichi.


“I can’t narrow it down to just one favorite coffee, but I would say that my favorite coffee is the coffee I have when I am traveling. I always try to find a specialty coffee shop in a city I don’t know anything about, but it’s not easy to find such a store, and I sometimes don’t drink coffee for a day or two. And when I drink a good cup of coffee after a few days of not drinking coffee in a different environment, the joy of drinking it makes me happier than the coffee I usually have.”