Name: Spicy Tuna Onigiri Recipe
Prep time: 15 min
Total time: 15 min
Cuisine: Japanese
Ingredients: 1/2 cup Kewpie mayonnaise (or American mayonnaise); 2 tablespoons masago; 1 tablespoon Sriracha; 1/2 lime, juiced; 8 ounces high quality raw tuna, minced; 3 tablespoons Kewpie mayonnaise (or American mayonnaise); 1 1/2 tablespoons Sriracha; 1 tablespoon soy sauce; 3 cups steamed short grain rice, warm; 2/3 cup furikake seasoning; 8 pieces nori, each 1.5″ x 3″

If you’re anything like me and love sushi but don’t always want the fuss of rolling or the trip to the restaurant, then this Spicy Tuna Onigiri Recipe is about to become your new best friend. These little rice triangles are packed with bold, spicy tuna flavor and wrapped in crisp nori—it’s sushi vibes, but way simpler and totally portable. Whether you’re meal prepping for work, packing a picnic, or just craving something savory and satisfying, these onigiri hit the spot every single time.

What I especially love about this Spicy Tuna Onigiri Recipe is how customizable it is and how quick it comes together. The creamy spicy tuna filling is balanced perfectly by the tangy masago sauce and the crunchy furikake seasoning on the outside adds a fun textural contrast. Trust me, once you get the hang of shaping the rice, you’ll feel like a pro and might even start making these for breakfast!

Ingredients You’ll Need

This recipe brings together simple ingredients that meld beautifully to create those soft, spicy bites you’re craving. I recommend using the best quality tuna you can find since it’s the star of the show—and having Kewpie mayo on hand makes a big flavor difference.

Kewpie (or American mayonnaise): Kewpie mayo offers a creamier, slightly sweeter taste that elevates the filling and masago sauce.
Masago: These tiny fish eggs add a lovely pop of umami and texture in the sauce.
Sriracha: The perfect spicy kick—adjust to taste if you want more or less heat.
Lime juice: Adds brightness and cuts through the richness of the mayo.
High quality raw tuna: Freshness is key here—go for sushi-grade for safety and flavor.
Soy sauce: Brings saltiness and depth to the tuna filling.
Steamed short grain rice: Use fresh, warm rice to help the onigiri stick together well.
Furikake seasoning: A Japanese rice seasoning blend that adds savory umami and crunch.
Nori sheets: These seaweed wraps hold it all together and add that classic sushi flavor.

Variations

I love making this Spicy Tuna Onigiri Recipe my own depending on what I have or my mood—there’s so much room for personalization! Don’t hesitate to experiment with your favorite sauces or seasonings.

Variation: Swap out raw tuna for cooked salmon or canned tuna if that’s easier or you prefer cooked fish—I’ve done both and they’re delicious!
Variation: Add finely chopped scallions or avocado to the filling for extra layers of flavor and creaminess.
Variation: For a vegan twist, try a spicy chickpea or mashed edamame filling with similar seasonings.
Variation: Use gluten-free soy sauce to keep things allergen-friendly without sacrificing taste.

How to Make Spicy Tuna Onigiri Recipe

Step 1: Whip Up the Masago Sauce

Start by mixing the Kewpie mayo, masago, Sriracha, and fresh lime juice in a bowl. This sauce is what gives the recipe its unique zing and creaminess, so stir until everything’s nicely combined and set it aside. I like to taste it and tweak the lime or Sriracha a bit here to get the perfect balance—do the same to suit your palate.

Step 2: Prepare the Spicy Tuna Filling

Next, mince the tuna finely—you want it break-apart tender, almost like a spread. In a bowl, combine the tuna with Kewpie mayo, Sriracha, and soy sauce until it’s all evenly mixed. The soy sauce adds a nice depth and saltiness, so be sure to mix well and adjust the heat if needed. This mixture should be creamy but not runny, perfect for stuffing inside your onigiri.

Step 3: Shape the Onigiri

This is the fun part! Take your warm short grain rice—warm is key to help it stick—and press about 1/4 cup into the bottom of an onigiri mold or your hand if you prefer. Create a small divot in the center, then spoon in a tablespoon of the tuna filling. Cover with another couple tablespoons of rice and press firmly with the mold top or your hands into a triangular shape. I usually dampen my fingers with water to prevent sticking—trust me, it helps a lot!

Step 4: Add Nori and Furikake

Once your triangle is nicely shaped, carefully remove it from the mold and wrap a strip of nori around the bottom. This not only adds classic flavor but also gives your fingers something to hold onto without squishing the rice. Then, gently press the sides into the furikake seasoning to coat the rice with extra umami and crunch. Repeat until you’ve used all your ingredients!

How to Serve Spicy Tuna Onigiri Recipe

The image shows a clear glass bowl on a wooden board filled with a pale pink chunky mixture that looks like shredded fish mixed with a creamy ingredient, with a metal spoon resting inside. Around the bowl, there are small white dishes: one with chopped green onions, one with a dark green seaweed mix sprinkled with white sesame seeds and red spices, and another with white sesame seeds. A closed blue and yellow can of Wild Planet tuna sits on the board near the dishes. The background has a white marbled surface with a white bowl holding lemons, a garlic bulb, and a glass bottle of olive oil, along with a silver metallic container and a salt and pepper set. photo taken with an iphone --ar 4:5 --v 7

Garnishes

I usually keep garnishes simple—sometimes a sprinkle of extra furikake or a few sesame seeds. But if I’m feeling fancy, I’ll add thinly sliced green onions or pickled ginger on the side for that zingy contrast. I also love serving with a little extra masago sauce for dipping because, why not? It’s addictively good.

Side Dishes

Some of my favorite sides with these onigiri are miso soup for warmth, a crisp Asian cucumber salad for freshness, or steamed edamame for a touch of protein. If you want a quick snack, a bowl of seaweed salad also pairs beautifully. It turns a simple lunch into a mini Japanese feast right at home!

Creative Ways to Present

I’ve found these Spicy Tuna Onigiri also make charming party appetizers. Try arranging them on a wooden board with small bowls of dipping sauces like extra Sriracha mayo or ponzu. For kids or special occasions, shaping the rice using plastic molds into fun shapes (like hearts or stars) really brings smiles around the table. Serving with colorful garnishes makes them look restaurant-grade in no time!

Make Ahead and Storage

Storing Leftovers

I usually store leftover onigiri in an airtight container in the fridge for up to 24 hours. Just be aware that rice tends to harden as it cools, so if you’re making these in advance, wrapping them tightly in plastic wrap individually keeps them moister. They’re still tasty cold, but I prefer to reheat them gently.

Freezing

Freezing onigiri is totally doable and comes in handy for quick snacks later. I wrap each piece tightly in plastic wrap, then place them in a freezer-safe bag. When ready to eat, defrost overnight in the fridge for best texture, though I won’t lie—the rice can get a little chewy compared to fresh.

Reheating

The key to keeping your onigiri tasting fresh is reheating gently. I usually microwave each wrapped in a damp paper towel for about 30 seconds to warm through without drying out the rice. You can also crisp the nori slightly by quickly toasting it in a dry pan if you’re feeling fancy. Just avoid overheating, or the tuna filling may get a little mushy.

FAQs

Can I use canned tuna for the Spicy Tuna Onigiri Recipe instead of raw tuna?

Yes! While fresh sushi-grade tuna gives the best texture and flavor, canned tuna can be a convenient and safe alternative. Just drain it well and mix it with the mayo, Sriracha, and soy sauce as you would the fresh tuna. The flavor will be slightly different but still delicious and satisfying.
How do I keep the rice from sticking to my hands or mold when shaping the onigiri?

Wet your hands or the onigiri mold with water before handling the rice. This simple trick prevents the sticky rice from clinging to your fingers and makes shaping much easier and less messy. You can also lightly salt your hands for extra flavor.
What type of rice is best for making onigiri?

Short grain Japanese rice is ideal because it’s sticky enough to hold its shape but still soft and fluffy. Avoid long grain rice, which tends to be too dry and won’t stick together properly for onigiri.
Can I make Spicy Tuna Onigiri Recipe vegan or vegetarian?

Absolutely! Swap the tuna for a spicy mixture of mashed chickpeas or edamame blended with vegan mayo, Sriracha, and soy sauce. You can also omit the masago sauce or find a vegan substitute to keep the flavors vibrant.
How spicy is this Spicy Tuna Onigiri Recipe?

The spice level comes mainly from the Sriracha, which you can adjust to your taste. I usually keep it moderate but if you love heat, feel free to add a little more. The creamy mayo helps balance the spice, making it flavorful but approachable for most palates.

Final Thoughts

This Spicy Tuna Onigiri Recipe is one of those dishes I return to over and over because it’s quick, satisfying, and feels like a little gift every time I bite into one. It’s sushi, but without the fuss—and every friend I’ve shared it with ends up loving the combination of creamy, spicy tuna and perfectly seasoned rice. So go ahead, give it a try in your kitchen—you just might find yourself hooked and making these delightful triangles as a regular part of your meal routine!