I have long been a fan of yuzukosho, a condiment made with the Japanese citrus fruit, yuzu, and chili peppers. The yellow-green paste gives an added kick to dishes with its fresh citrusy aroma and spicy zing. It is a delicious accompaniment to grilled chicken, fish or roast beef, or simply mixed into the soup of a hotpot.

In recent years, yuzukosho has been discovered by the culinary world outside Japan and re-discovered in its home market — becoming one of those versatile ingredients, like wasabi and matcha, that are being used in new ways by innovative chefs, patissiers and food producers.

The creative uses of wasabi, the nose-tingling, spicy condiment which is generally associated with sashimi and sushi but has more recently cropped up in unlikely dishes such as soft-serve ice cream or  mixed into cookie batter, are well known. 

And matcha, which is traditionally a very bitter and bright green powdered tea, has become a popular flavor in a wide range of sweets, from chocolates and puddings to ice cream. 

But it was only when I was invited to a yuzokosho-making workshop that I discovered the variety of foods that yuzukosho can embellish.

The workshop was held at Zarai, a restaurant featuring the cuisine of Oita Prefecture, on the southwestern island of Kyushu, which is famous for its yuzukosho. Zarai also houses a shop promoting the regional goods of Oita.

Our workshop instructor, Yoshie Kamiya, who hails from Oita, is famous for her deep knowledge of and relationship with yuzu, and is affectionately known as “Madam Yuzu.”

madam yuzu

“Madam Yuzu” explains how to make yuzukosho, while the Zarai chef chops yuzu peel.

According to Kamiya, yuzukosho – or yuzugosho, as it is known in Oita – was first made in her home province, which is famous for its yuzu production, although recently nearby Fukuoka Prefecture has been laying claim to that title. 

Wherever its origins, yuzukosho has become a popular condiment all over Japan and is even sold in tubes alongside wasabi, Japanese mustard and ginger.

yuzu kosho tools

The table is set with all the tools and ingredients needed to make yuzukosho. The food processor was shared among several tables.

The first step in making yuzukosho is to peel the washed yuzu. As the Zarai chef deftly peels a yuzu by a knife wielded with samurai precision, Kamiya tells us that it is just as acceptable to peel the fruit with your hands. 

The peel is then chopped into smaller pieces so that it can be ground with the peppers in a food processor. Although green chili peppers are more commonly used for yuzukosho, we were provided with the less well-known yellow peppers, which some of us had never even seen before. Kamiya warned us to wear our plastic gloves and be very careful with the yellow peppers, which are much stronger than green or red peppers. 

After removing their stems, the peppers should be sliced in half and the seeds removed. This is an important part of the process as pepper seeds somehow manage to find their way into the yuzukosho and ruin the smooth texture, no matter how carefully you think you have removed them. 

Next, throw the chopped yuzu peel, sliced peppers and some salt – about 16 per cent of the weight of the yuzu peel –  into the food processor and let it whizz on top strength until the concoction is blended into a pure paste.

The resulting mixture still needs to be smoothed out, in part to make sure there aren’t any leftover seeds. This is done in the traditional way, by hand, in a suribachi grinding bowl with a wooden surikogi, which are essentially a Japanese mortar and pestle. Sure enough, several seeds had escaped the eyes of our team members in charge of cutting the yellow peppers.

Grinding the yuzukosho into a smooth paste in a suribachi bowl with a surikogi.

When the unwanted seeds are removed, the yuzukosho is ready for consumption. 

We are presented with the bright yellow yuzukosho we made in eye-catching containers.

We were able to taste the yuzukosho we made at lunch, which featured many dishes popular in Oita, such as chicken tempura.

The appetizers included peanut tofu with yuzukosho, mochi (rice cakes) made with gingko nuts, a slice of octopus and various vegetables.

Yellowtail and sea bream sashimi served with yuzukosho.

chicken tempura

The chicken tempura was very tender and crispy on the outside.

Shrimp, lotus root and finely shredded egg crepe on vinegared rice, with miso soup.

Compared to yuzukosho made with green peppers, our yuzukosho was a bright yellow and had less of a kick, despite Kamiya’s warning about the piquancy of yellow peppers.

Nevertheless, our freshly made yuzukosho complimented all the dishes served, such as a peanut tofu appetizer and even the yellowtail and sea bream sashimi, which would normally be paired with soy sauce and wasabi, rather than yuzukosho.

The biggest surprise was the dessert of sweet bean paste and white chocolate ice cream with a topping of – what else? Yuzukosho!


An ice cream of white chocolate served with yuzukosho and an assortment of dry cakes.