If you’ve ever wandered through a Japanese convenience store, chances are you’ve spotted those neatly wrapped little rice triangles called onigiri. They’re the ultimate grab-and-go snack in Japan—simple, portable, and oh-so-satisfying. Today, we’re making a version that packs a little heat: Spicy Tuna Onigiri.
These Japanese rice balls are a dream for busy days when you need something quick but filling. The creamy tuna mayo filling gets a spicy kick from sriracha, making them both comforting and exciting. And here’s the best part: this easy onigiri recipe comes together in just 20 minutes with only a few pantry staples.
Think of it as your new go-to snack for road trips, work lunches, or even cozy Netflix nights. Plus, there’s something fun about shaping rice into little triangles—it feels nostalgic and playful, almost like edible origami. So, let’s roll up our sleeves (and maybe keep a damp towel handy for sticky fingers) and make these irresistible rice bundles together.
Why You’ll Love This Spicy Tuna Onigiri
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A flavor-packed spin on traditional Japanese rice balls.
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Ready in just 20 minutes—perfect for busy days.
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Portable, mess-free, and easy to pack for picnics or lunches.
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Customizable with toppings like sesame seeds or extra nori.
Ingredients
For the Rice:
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3 cups cooked short-grain rice (about 675 g)
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1/2 sheet nori (cut into strips) or 2 sheets for extra wrapping
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1/2 tsp salt (3 g)
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1/2 tsp black sesame seeds or toasted sesame seeds (optional, 2 g)
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Water (for moistening rice paddle)
Spicy Tuna Filling:
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5.29 oz canned tuna in oil (150 g, drained well)
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2 tbsp mayonnaise (30 g)
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1 tbsp sriracha sauce or other hot sauce (15 ml)
Steps
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Transfer freshly cooked or reheated rice into a large bowl. Season with salt and mix well. Keep covered and warm.
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Drain tuna thoroughly using a sieve, pressing with a fork to remove excess liquid. Mix tuna with mayonnaise and sriracha until creamy.
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Lay a 15 x 15 in (38 x 38 cm) sheet of plastic wrap on a flat surface. Moisten your rice paddle with water and divide rice into 4 equal portions.
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Place 3/4 cup rice (about 170 g) onto the wrap, spreading into a circle about 1.25 cm thick.
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Add a spoonful of tuna filling in the center. Lift the corners of the plastic wrap, shaping rice around filling into a ball.
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Gently flatten into a triangle shape about 4.5 cm thick using your hands.
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Wrap a strip of nori around the base (rough side facing the rice). Garnish with sesame seeds if desired.
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Serve warm or wrap tightly for later.
Tips for the Perfect Onigiri
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Keep your hands damp. Rice is sticky by nature, and a little water keeps it from clinging to your fingers.
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Use short-grain rice. Long-grain won’t hold its shape as well—onigiri needs that stickiness to stay together.
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Adjust the spice. Love it fiery? Add more sriracha. Prefer it mild? Cut back and let the creamy mayo balance things out.
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Plastic wrap is your friend. It makes shaping the rice easier and keeps the filling neatly tucked inside.
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Add crunch. A sprinkle of sesame seeds or even crushed seaweed snacks adds texture and flavor.
A Little Story from My Kitchen
The first time I tried onigiri was at a train station in Tokyo. Rows upon rows of rice balls, each with different fillings, all wrapped up like perfect little presents. I grabbed one with tuna mayo—simple, creamy, and delicious. But when I got home, I craved something with a bit more personality. Enter sriracha.
That one spoonful of heat turned a familiar snack into something bold and addictive. Now, whenever I pack these for road trips or my kids’ lunchboxes, the spicy tuna ones always disappear first. They’re a little nostalgic and a little adventurous, which sums up my cooking style pretty well.
What to Serve with Spicy Tuna Onigiri
These rice balls are great solo, but they shine even more when paired with:
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A light miso soup for a cozy, complete meal.
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Pickled vegetables for tangy contrast.
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A fresh cucumber salad to balance the spice.
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Green tea or iced matcha for a refreshing sip.
If you’re serving them as part of a bigger spread, mix in other onigiri flavors—like plain salted rice balls or ones with salmon—for variety.
How to Store Leftovers
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Room temperature: Eat within 6 hours if left wrapped tightly. Onigiri is traditionally eaten fresh!
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Refrigerator: Store in an airtight container for up to 1 day, but note that the rice may harden. A quick microwave (10–15 seconds with a damp paper towel on top) helps restore softness.
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Freezer: Not recommended, as the rice tends to dry out.
Tip: If you know you’ll be storing them, keep the nori separate until just before eating. That way, it stays crisp instead of turning soggy.
FAQs
Can I make Spicy Tuna Onigiri ahead of time?
Yes! They’re perfect for meal prep, but best enjoyed the same day for freshest taste.
What kind of rice should I use?
Short-grain Japanese rice (sushi rice) is best. Medium-grain works in a pinch, but avoid long-grain varieties.
Can I swap the filling?
Definitely! Try salmon, chicken, or even avocado for different flavors. The method stays the same.
Do I have to use plastic wrap?
Not at all—traditionally, onigiri is shaped with damp hands. Plastic wrap just makes it a little easier and less messy.
Wrapping It All Up
There’s a reason Spicy Tuna Onigiri is a fan favorite—it’s quick, flavorful, and endlessly versatile. With just rice, tuna, mayo, and a splash of hot sauce, you’ve got a snack that feels like a treat but takes no time at all.
Whether you’re whipping them up for a picnic, packing school lunches, or sneaking a midnight bite, these Japanese rice balls deliver comfort and flavor in every bite. Once you try this version, you may find yourself making onigiri part of your weekly routine—and honestly, your taste buds will thank you.
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Print
Quick & Easy Spicy Tuna Onigiri
- Total Time: 20 minutes
- Yield: 4 pieces 1x
Description
Quick & Easy Spicy Tuna Onigiri is a fun, flavorful twist on Japanese rice balls. Tender, seasoned short-grain rice is filled with creamy tuna mayo spiked with sriracha for a kick, then shaped into portable triangles wrapped in nori. Perfect for lunches, picnics, road trips, or a cozy snack, these onigiri are fast to make (just 20 minutes) and endlessly customizable.
Ingredients
For the Rice:
-
3 cups cooked short-grain rice (about 675 g)
-
1/2 sheet nori (cut into strips) or 2 full sheets for extra wrapping
-
1/2 tsp salt (3 g)
-
1/2 tsp black or toasted sesame seeds (optional, 2 g)
-
Water (for moistening rice paddle)
Spicy Tuna Filling:
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5.29 oz canned tuna in oil (150 g, drained well)
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2 tbsp mayonnaise (30 g)
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1 tbsp sriracha sauce or other hot sauce (15 ml)
Instructions
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Transfer cooked rice to a large bowl, season with salt, and mix well. Keep covered and warm.
-
Drain tuna thoroughly, pressing out extra liquid. Mix tuna with mayonnaise and sriracha until smooth.
-
Lay a 15 x 15 in (38 x 38 cm) piece of plastic wrap on a flat surface. Moisten your rice paddle with water and divide rice into 4 equal portions.
-
Place 3/4 cup rice (about 170 g) onto the wrap, spreading into a circle about 1.25 cm thick.
-
Add a spoonful of tuna filling to the center. Lift plastic wrap corners and shape rice around filling into a ball.
-
Gently flatten into a triangle about 4.5 cm thick. Wrap a strip of nori around the base (rough side facing rice). Garnish with sesame seeds if desired.
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Serve warm or wrap tightly for later.
Notes
Keep hands damp when shaping rice to prevent sticking.
Use short-grain rice for the best texture and hold.
Adjust sriracha to taste for more or less heat.
If storing, keep nori separate until serving to maintain crispness.
- Prep Time: 20 minutes
- Cook Time: 0minutes
- Category: Snack / Appetizer
- Method: No-Cook Assembly
- Cuisine: Japanese