How to Make Delicious Onigiri According to a Famous, Established Onigiri Restaurant

"Onigiri" rice balls are something that you see everywhere in Japan, especially at convenience stores. Despite being a simple food made of just four ingredients - rice, salt, seaweed, and whatever fillings you want - there are actually many ways to elevate this Japanese dish. For this edition of our deep-dive series "Culture of Japan," we reached out to popular Tokyo onigiri shop "Onigiri Bongo" to teach us all the hidden tricks behind making delicious onigiri, from the best way to cook the rice to how much to use and how to shape the rice ball!

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Onigiri - A Common Food That the Japanese Have Loved for Ages

"Onigiri" is a traditional Japanese food beloved by the masses. It is a simple dish, made by wrapping some ingredients in rice and shaping the mass into a triangle, ball, etc. You'll see people eating onigiri in a wide variety of situations, from hiking trips to lunches for hanami or school field days.

As a traditional Japanese dish, onigiri has been in Japanese people's lives since long ago, making an appearance in countless ancient books and documents. However, it didn't become a convenience food until the Edo Period (1603-1867), when travelers started carrying it around and farmers ate it as a simple and quick meal.

Onigiri was originally eaten as is, without any seaweed wrapping. Once the Japanese became able to cultivate seaweed, however, more and more people started eating onigiri wrapped with seaweed. This is because there were several advantages to doing so - the rice stuck less to the hands, and the seaweed gave the dish extra nutritional value. The people of Kansai in particular started favoring onigiri wrapped with flavored seaweed thanks to Kyoto and their penchant for flavoring their seaweed with soy sauce and mirin.

How Convenience Stores Shaped the Onigiri of Today

When discussing the history of onigiri, it is impossible not to mention how convenience stores have helped the dish proliferate into the lives of the everyday Japanese.

In 1978, the convenience store giant 7-11 became the first to commercialize onigiri. Straying away from its traditional format that required people to carry it around in some kind of box, 7-11 put the onigiri rice ball and seaweed separately into their own little plastic packets. Right before eating, people would rip them out of their plastic packaging and combine them. This type of packaging allowed the seaweed to stay crispy while still keeping customers' hands mess free. In other words, it was an innovation that better matched the needs of modern consumers. Needless to say, it blew up in popularity, and since then onigiri has become one of the mainstay products of Japanese convenience stores.

The Flavors of Onigiri Are Endless

One of the best features of onigiri is that you can use anything to make it - Japanese ingredients, whatever you have locally, seafood, vegetables, etc. Simply wrap them in rice or mix them with the rice and, before you know it, you'll have onigiri!

Onigiri is a creative dish that can be freely adjusted to suit the person eating it, the place, and the purpose. This style of eating truly embodies the eating habits of the Japanese people.

The Many Shapes of Onigiri

There are no clear rules for the shape of onigiri. It can be shaped however you like - cylindrical like a straw bale, flat and round like a pancake, round like a ball, etc.

The triangular shape that most of us are familiar with is believed to have originated from the ancient religion of "Shugendo," where people believed that gods dwelled in the mountains. By eating triangular, mountain-shaped onigiri, worshipers could "consume" the grand spiritual power of the mountains.

However, plenty of other theories behind the triangular shape of onigiri exist, some more practical than others. For example, some believe that it became popular because the triangular shape made it easy to hold and carry, or because it looked extremely nice when put up for display.

By the way, as an interesting tidbit, did you know that "onigiri" is also referred to as "omusubi" in Japan? Both mean the exact same thing, and you'll see both versions during your travels around Japan. For example, Lawson calls them "onigiri" while FamilyMart refers to the food as "omusubi." Keep your eyes peeled for this the next time you're in Japan!

Popular Onigiri Shop’s Secret Tips on Making Delicious Onigiri

Onigiri can be found in many shops and restaurants today, but if you wanted to make it at home, how can you make it as delicious as possible? We asked Yumiko Ukon, the proprietress of popular onigiri restaurant "Onigiri Bongo" which has been running in Tokyo's Otsuka area for over 60 years, to share her secrets for making delicious onigiri at home.

The Best Rice for Onigiri and How to Cook It

It all starts with the rice, the most fundamental part of any onigiri. Choose a rice variety with large and firm grains so that they don't get easily crushed after being cooked, shaped, etc. This is important because crushing the rice causes the starch in it to overflow, resulting in an unpleasant gooey texture. You should especially look out for rice that's nice and shiny, as it'll really plump up the appearance and texture of the onigiri when you shape it.

After washing the rice (skippable if you have pre-washed rice), soak it in clean water at room temperature for about an hour, then drain with a colander and place it into the fridge to rest overnight. Chilling rice converts the starch in it into sugar, bringing out the sweetness of the rice even more. Then the next day, you can just cook it like normal.

Tips on Shaping the Onigiri

Making delicious rice is half the battle of making a good onigiri! If you want to take your game one step further, you should pay attention to the temperature of the rice. Freshly cooked rice lets off steam which can make the rice grains stick together. To avoid this, use a rice scoop to fluff up the rice, then wait for it to cool off to 60-70℃ before using it.

As for the ratio of rice to ingredients, that's completely up to the chef's discretion. That said, what you want is balance. Have you ever had the experience of biting into an onigiri, only to taste nothing but rice? To avoid this type of scenario, Onigiri Bongo recommends a 2:1 rice to filling ratio.

When you're finally ready to shape the rice balls, take the time to lightly wet your hands with water first. This makes it harder for the rice grains to stick to your hands.

Finally, when you're shaping the rice balls, take care to not use too much force! In Japanese, "onigiri" means "to grab." But putting too much force can actually be detrimental, as you'll make the onigiri too firm and compact. So, be careful!

So, how does Onigiri Bongo do it? Well, according to Ukon, they form the rice into a slightly round shape, then they create a hollow in the middle and stuff the filling into it. Next, they take the same amount of rice and place it on top, making sure to leave space in the middle like you would for a burger or sandwich. This prevents the rice from squishing the filling.

To finish it off, they gently use their hands to close any gaps between the two layers of rice, rather than firmly gripping or shaping the rice ball. This method keeps the rice nice and fluffy.

How to Eat Fluffy, Filled-to-the-Brim Onigiri

Of course, it's most recommended to eat onigiri as soon as they're made. They taste completely different from the cold onigiri you get at a convenience store! Japanese people even say that when they eat a warm onigiri, they can "feel" the warmth of the hands that made it.

However, freshly made, fluffy onigiri that's filled to the brim can easily fall apart or spill over when eaten. We were told that the best way to prevent this is by eating from the bottom instead of the top. The seaweed will keep the rice and ingredients from spilling over when you eat it this way!

Onigiri Bongo - A Long-Beloved Onigiri Shop With 56 Flavors on the Menu

We hope you've learned enough now on how to choose the right rice, cook it, and shape it to make delicious onigiri. However, we can't forget about the other main part of onigiri which is, well, the filling.

Getting to choose and use whatever ingredients you want is one of the fun parts of making onigiri, but there's normally a limit to how many ingredients you can work with in a home kitchen. So, if you want to try out a variety of flavor combinations, come over to Onigiri Bongo! This long-established onigiri store in Tokyo's Otsuka area has a whopping 56 onigiri flavors to choose from. You'll surely be able to find something you like!

Among the 56 flavors, you'll find standard choices like salmon, cod roe, and salmon roe, as well as more unusual ones such as curry, beef tendon, minced meat, peanut miso, and cheese bacon. They're always adding to the list - for example, in 2021, they added peperoncino to their menu.

You can choose two or more ingredients to freely combine together into one onigiri, and for a little extra cash, you can even ask to add cream cheese or mayonnaise to the mix. This freedom of choice is truly something unique to Onigiri Bongo!

This wide variety has not come at the cost of quality. Onigiri Bongo is very particular about everything they use.

For example, the rice is the Koshihikari variety from Iwafune in Niigata Prefecture. The large temperature difference between morning and night there makes incredibly sweet rice, and the area's rich natural environment also helps the rice grow large and beautiful. As for the seaweed, they only use those grown in Ariake, Saga Prefecture, as they are very aromatic and rich in amino acids. Even their salt, which comes from Okinawa, is a type that's incredibly mineral rich and contains little bitterness.

Every ingredient is thoroughly researched - from the amount of salt needed to how each ingredient is prepared - to ensure they're a perfect match with each other and the rice.

Onigiri Bongo puts their utmost into every aspect of their business: selecting the best ingredients, having a large menu, only making the onigiri once an order comes in like at a fancy sushi restaurant, creating onigiri that are twice the size of your standard rice ball, and so on. So, it's no wonder that their onigiri tastes a level above the rest and that they get lines of customers out their doors! They even have customers who, after eating onigiri there, order some more to take home!

As for the most popular flavors, the Japanese have always preferred more standard choices like plum and salmon roe, but recently there's been an increase in young people who order mayonnaise-flavored onigiri. Ukon isn't a fan, but she added it to the menu after seeing its growing popularity, and it is now an extremely popular flavor today. "Young people will add mayonnaise to anything!" she remarked with a laugh.

Onigiri Bongo's fame has also attracted hordes of customers from all over the world. Preferences differ from country to country, but a general favorite seems to be any kind of seafood onigiri. The onigiri shop also has some more foreign cuisine-inspired flavors like pork kimchi, which some foreign customers have mentioned to be "like a breath of fresh air" when it comes to onigiri flavor choices.

Their menu comes in several different languages, but if you don't read any of those, every menu item has its own number, so you can just point to what you want to eat.

►If you want to learn more about Onigiri Bongo and Ukon the proprietress, take a look at this article: [to be added later]

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Try Your Hand at Making and Eating Onigiri!

The beauty of onigiri is that you can enjoy a combination of elements all at once: the fluffy texture and warmth of the rice, the crispy seaweed, and whatever ingredients you like! Onigiri may seem easy to make at a glance, but there's actually technique and a lot of thought involved. Try making some at home using the tips in this article! And the next time you get the chance to visit Tokyo, make a stop at Onigiri Bongo to try their creations filled with over 60 years of love and hard work!

If you want to give feedback on any of our articles, you have an idea that you'd really like to see come to life, or you just have a question on Japan, hit us up on our FacebookTwitter, or Instagram!

Kanto Feature

The information in this article is accurate at the time of publication.

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About the author

Fuchi Pan
Born in Taiwan, currently living in Tokyo. Yearning for a life surrounded by handmade goods and things she loves.
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