Onigiri 101: How to Make Japanese Rice Balls

Every other week, Anna Hezel talks about the innovations, decorations, and other quiet touches that make a party memorable.

Today: Everything you need to know about making this food truck treat at home.

We think of sandwiches, granola bars, and muffins as great on-the-go snacks. But rice? In most cities in the U.S., you'd be hard-pressed to find a commuter snacking on rice (unless it's puffed and in the form of a cereal bar). The same is not true in Japan—balls of cooked rice called onigiri or omusubi are sold in convenience stores, elaborate food halls in department store basements, and specialty takeout restaurants. Onigiri are a version of Japanese rice balls made from sushi rice packed tightly around a salty filling of seafood or vegetables. Compact and practical, these little savory packages have long been a staple of bento boxes and Japanese delis. Recently, they have enjoyed a surge of popularity among food trucks, where they are made fresh and grilled lightly to order. These savory and utensil-free snacks come in a variety of flavors and designs—some are even shaped like animals!—and wrapped in a sleeve of crisp seaweed (thus, napkin-free, too).

While the Japanese food truck variety might set you back $4 or $5 a pop, making onigiri at home is irresistibly economical and easy. For the price of a small piece of fish and a cup of rice, you can create for yourself a full week's worth of lunches using salted salmon, sesame seeds, and sticky short-grain rice. With the addition of some nori seaweed, a pair of scissors, and a touch of creativity, you can craft all sorts of kid-friendly varieties, ranging from pandas to pigs to ninjas.

If you're in the mood for a warm meal, just toast your onigiri lightly for 2 to 3 minutes per side on a pan brushed with sesame oil. The outer layer of rice will get toasty and golden-brown and a little bit crackly.

Traditional fillings:

A traditional onigiri recipe calls for a filling of cod roe, pickled plums, or teriyaki salmon. But don’t let the fun stop there. For other variations, try smoked salmon and scallions, sautéed kabocha squash, or Trent Pierce's Miso-Creamed Kale. Less traditional but equally delicious fillings include pickled mustard greens, okaka (bonito flakes simmered in a sake-spiked sweet soy, sautéed shiitake mushrooms, miso scallions, mashed sweet potato or squash, pickled burdock root, scrambled egg, hijiki or other seaweeds, mashed and salted avocado, and canned tuna mixed with a touch of mayo. Don't hesitate to add flavor—in the form of red pepper flakes or soy sauce or more of anything you've already mixed into the rice—at this stage, too.

Finally, make sure to finely chop any of the larger ingredients (sautéed mushrooms, for example) and to mash and mix well, as each onigiri can only accommodate a small amount of filling.

Toppings:

Onigiri is just as much about the fillings as it is the toppings. You’ll need seaweed (sushi-style nori), black and white sesame seeds, and shichimi togarashi (a Japanese spice blend made up of ground sesame seeds, orange peel, and chili pepper). 

Instructions:

Onigiri can be made with sushi rice or any short-grain white rice seasoned with furikake or rice flavoring. Cook a pot of sushi rice on the stovetop or using a rice cooker, and keep the rice slightly warm. Four cups of cooked rice will be enough for about 10 to 12 rice balls. Set a bowl of cold water at your work space so that you can continuously wet your hands as you form the rice balls. This will prevent the rice from sticking to your hands.

Wet your hands and scoop up a small handful of the rice. Squeeze the rice to remove any excess water and then flatten the rice into a dense, thin, oblong layer in the palm of your hand. Scoop a small spoonful of the filling into the center of the rice, and gently fold the rice around the filling. Using both hands, pack the rice into a firm ball and then gently press it into whatever shape you'd like. You can also use plastic wrap. I like flattened triangles because they are easy to bite into.

At this point, you can roll your rice ball in some sesame seeds, sprinkle with shichimi togarashi, or wrap the onigiri with a strip of seaweed around it. If you want to be fancy, you can use your kitchen shears to cut little shapes out of the seaweed. Two semicircles, two ovals, a little triangle of a nose, and a pointy little sliver of a mouth gives you a panda. You can also make yaki onigiri, which are grilled Japanese rice balls that are pleasingly crispy.

Serve with good-quality soy sauce for dipping. 

What's your favorite onigiri filling? Tell us below in the comments.