How to make Tuna Mayo Onigiri and Onigirazu

If you are new to Japanese homecooked meals, you probably have never heard of Onigiri, let alone Tuna Mayo Onigirazu.

Onigiri is a hand molded, triangle rice ball, wrapped in seaweed, with some flavorful filling in the center.  Onigiri has been around for centuries in Japan as a portable lunch food.   It is the staple food for picnics and packed lunches today; just as sandwiches are to the western countries.  It almost always looks something like this:

What is Onigirazu?

Onigirazu, on the other hand is a more recent creation (by a Japanese dad blogger, nonetheless!) and a slight divergence from Onigiri only in how it is assembled.  Because it does not require any hand molding of the rice, Onigirazu is easier and perhaps less messy to make.  But all the essential ingredients are the same – rice, seaweed and your favorite fillings in the center. 

It’s not sushi!

While they may look similar, onigiri and onigirazu are different from sushi.  Sushi is made with vinegared rice, whereas onigiri and onigirazu are made with plain Japanese rice.  Raw fish is hardly ever used as an ingredient for onigiri and onigirazu. 

Onigirazu filling options

Most typical and traditional fillings are ume (pickled plum), salmon, shaved bonito flakes and cod roe.  But you can put any type of ingredients that you might put in your sandwich here – eggs, lettuce, ham, avocado, cucumbers…even Spam! Tuna Mayo filling is a relatively modern filling option that has gained popularity in Japan.  Once you try it, you’ll understand the reason for its popularity.  It’s simple yet delicious.

Tips to making onigiri and onigirazu

Just a few useful tips to keep in mind when you are making onigiri or onigirazu:

• Be sure to use Japanese rice.  You can’t use any other types of rice since they will not be as sticky as the Japanese rice and will not hold the form well. Here are 5 simple tips on how to cook perfect Japanese rice.
• Don’t use hot rice.  Let the rice cool down before making onigiri/onigirazu.  Using hot rice will make it too hot to handle plus the high heat will make the seaweed shrivel.  
• Don’t put filling directly on seaweed.  In other words, make sure that filling is completely encased with rice before applying the seaweed to the rice.  Otherwise, the filling will make the seaweed soggy and briny. 

How to make tuna mayo filling

Making the tuna mayo filling is easy:

Ingredients: 

• 1 can tuna, in water
• 2 teaspoon Mentsuyu
• 4 teaspoon Japanese mayonnaise

Instructions:

1. Drain tuna in strainer, squeezing out as much water as possible with a spoon
2. In a small bowl, mix tuna, mentsuyu and Japanese mayonnaise 

How to make tuna mayo onigirazu – 2 servings

Ingredients:

• Tuna mayo filling
• 2 cups cooked rice
• 2 sheets nori (seaweed) 
• Salt
• Optional filling: sliced cucumbers (seedless, English or Japanese cucumbers)

Instructions:

1. Cut a plastic wrap larger than the sheet of seaweed.  Lay it down flat. Lay the seaweed on the plastic wrap, glossy side down. Sprinkle a pinch of salt in the middle.
2. Place ½ cup of rice in the center.  Mold it into a square.
3. Spread half of the tuna mayo filling over rice.  
4. Arrange cucumber slices over mayo filling.
5. Spread ½ cup of rice over cucumbers, making sure that the rice covers all the cucumbers and tuna.  Sprinkle some salt on rice.
6. Fold the nori over the rice as if you are wrapping a present, tucking the corners in as you go.
7. Wrap the plastic wrap around the nori-wrapped rice.  Let it sit for at least a few minutes.  
8. Remove the plastic wrap before serving. 

If you love tuna mayo: Try our tuna mayo pasta salad recipe!

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