Japanese Tuna Mayo Onigiri Rice Ball (with Spicy Option)
Bring a touch of 7-Eleven Japan into your home! This tuna mayo onigiri has a perfect tuna-mayo balance, with mentsuyu adding rich flavor to this simple rice ball.
Ingredients
- 1 cup uncooked Japanese short-grain white rice 240ml (see Note 1)
- 1 cup + 2 tablespoons water 266ml
- 1 teaspoon mentsuyu (see Note 2)
- kosher salt
For the Tuna Mayo
- 2.5 ounces canned tuna drained, about half of a small American canned tuna
- 2 tablespoons Japanese mayonnaise
- 1 teaspoon mentsuyu (see Note 2)
- ⅛ teaspoon ground black pepper
Instructions
- Rinse the Rice: Start by rinsing 1 cup uncooked Japanese short-grain white rice about three times until the water runs clear.
- Cook the rice:- Rice Cooker/Slow Cooker: Add the rinsed rice and 1 cup + 2 tablespoons water. Soak for at least 30 minutes, then cook as usual.- Stovetop: Add the rinsed rice and 1 cup + 2 tablespoons water to a pot. Soak for 30 minutes, then cover and heat on medium until it boils. Lower the heat and simmer for 15 minutes. Turn off the heat and let it steam, covered, for 10 minutes. Don’t lift the lid during this step—you want to keep all the heat and steam in!
- Make the tuna mayo: Mealwhile, drain 2.5 ounces canned tuna well (see Note 3). Mix it with 2 tablespoons Japanese mayonnaise, 1 teaspoon mentsuyu, and ⅛ teaspoon ground black pepper until it’s creamy.
- Season the rice: Once the rice is done, fluff it with a rice paddle to let out the extra steam, then mix in 1 teaspoon mentsuyu while it’s still warm.
- Shape the onigiri: You can shape your onigiri with either your hands or plastic wrap—whichever works best for you!If you're using your hands, wet them, sprinkle a tiny pinch of salt, and rub your palms together to dissolve the salt. If using plastic wrap, sprinkle the salt directly onto it.Next, divide the rice and tuna mayo into portions. For each onigiri, place half of the rice in your hand or on the plastic wrap, add the tuna mayo filling, then cover it with the remaining rice. If using plastic wrap, sprinkle another tiny pinch of salt on top. Press and turn to shape it into a triangle (see Note 4).
- Enjoy: Wrap with nori before serving if you like, and enjoy!
Notes
- (Note 1-1) Using Leftover Rice: If you already have cooked rice, you’ll need about 3 cups (455g) for four onigiri. Simply microwave the rice to warm it up. However, I recommend using freshly cooked rice for the best results.
- (Note 1-2) Types of Rice: For the best results, use Japanese short-grain rice like Koshihikari, but medium-grain options like Nishiki or Botan work well too. Avoid using other types of rice, like Jasmine.
- (Note 2) Mentsuyu: This Japanese noodle soup base adds umami, sweetness, and saltiness in one go. I used Kikkoman Hontsuyu (4x concentrated), but for 3x, use 1 ⅓ teaspoons instead of 1 teaspoon.
- (Note 3) Drain The Tuna Well: Squeeze out as much moisture as possible from the canned tuna to keep your onigiri from getting soggy.
- (Note 4-1) Shaping Onigiri: When shaping your onigiri, try not to press the rice too hard. You want it firm enough to hold its triangle shape, but soft enough to fall apart when you eat it. That’s why I recommend skipping the onigiri molds that make you press the rice down. For more shaping tips, check out the step-by-step instructions.
- (Note 4-2) Onigiri Mold: If you really want to use an onigiri mold, look for one that doesn’t press the rice too hard—too much pressure can make the onigiri dense. Instead, choose a mold that lets you shape the rice gently with a rice paddle. The TIKUSAN Onigiri Mold Musubi Maker is a great option!
