Copycat 7-Eleven Style Japanese Tuna Mayo Onigiri 🍙

The Ultimate Comfort Food: Japanese Tuna Mayo Onigiri (7-Eleven Style Recipe) 🍙

Tuna Mayo is the undisputed king of Japanese convenience store (konbini) rice balls, holding the #1 spot in popularity rankings for decades. Among them, the “Wafu (Japanese-style) Tuna Mayo” from 7-Eleven is a personal favorite.

What makes it special? The soft, moist seaweed (nori) wrapping and the deeply seasoned rice. This recipe is a perfect recreation of that iconic taste. The secret lies in seasoning the rice while it cooks with salt and Shiro-dashi (white dashi), ensuring a rich, uniform flavor in every bite.

Pro Tips for the Perfect Onigiri:

Balance is Key: Don’t overstuff! A 1:4 ratio of filling to rice is the “Golden Ratio” to prevent the ball from falling apart.
Watch the Moisture: Drain the tuna oil thoroughly. Too much liquid will make the rice ball crumble.
Hygiene First: For food safety, many people now use plastic wrap or onigiri molds instead of bare hands.

Nutritional Info (Per Onigiri)

Yields 6 rice balls

Calories: ~235 kcal
Protein: ~7.2g
Fat: ~9.8g
Carbs: ~28.5g
Sodium: ~640mg

Ingredients (Makes 6 Rice Balls)

For the Rice:

Rice: 320g
Salt: 6g
Shiro-dashi: 6g
Water: 360g

For the Filling & Wrap:

Canned Tuna (in oil): 150g
Mayonnaise: 36g
Sugar: 3g
Shiro-dashi: 6g
Nori (Seaweed): 6 sheets

Instructions

Step 1: Prep the Rice

Wash 320g of rice until the water runs clear.
Add 6g salt, 6g Shiro-dashi, and 360g water.
Crucial: Let the rice soak for at least 30 minutes before starting the rice cooker. This ensures a smooth, fluffy texture.
Cook the rice as usual.

Step 2: Prepare the Tuna Mayo

The most important step for structure: Thoroughly drain the excess oil and moisture from the 150g tuna.
In a bowl, mix the drained tuna with 36g mayonnaise, 3g sugar, and 6g Shiro-dashi until well combined.

Step 3: Assemble

Place a portion of rice in your hand (with wrap) or a mold.
Add the tuna mayo mixture in the center and cover with more rice.
Shape into the classic triangle.
The Seaweed Wrap:
- For Moist Nori (Soft style): Wrap while the rice is still warm.
- For Crispy Nori (Crunchy style): Wrap immediately before eating.

Watch the full process here:

Want more Tuna Mayo ideas?

Tuna mayo is incredibly versatile! Try these variations:

🥗 Tuna Mayo & Garland Chrysanthemum (Shungiku) Salad: A unique and refreshing side dish. 👉 Tunamayo shungiku (Chrysanthemums mayonnaise salad)
🍝 Tuna Mayo Pasta: Season your noodles with soy sauce, mirin, and dashi powder for a quick Japanese-style meal.
📖Related Link: Read the Japanese version of this article here! []

naokoan

Hi, I’m Naoko! I am a licensed Registered Dietitian in Japan, currently working in a hospital setting. My daily mission is to provide nutritious, healing meals to patients, ensuring that every dish supports their health and brings a smile to their face. My recipes are more than just cooking guides—they are built on scientific nutritional balance and clinical experience. Why I provide ingredients in grams (g): You might notice that all my recipes use precise gram measurements. This is because, as a dietitian, I believe that accuracy is the key to true health management. Whether you are tracking calories, managing salt intake, or simply want to recreate the exact flavor of a professional hospital kitchen, these measurements ensure your success and well-being. My Specialty: I specialize in high-pressure cooking and oven recipes that save time without sacrificing nutrition. My goal is to introduce the world to “Real Japanese Home Cooking”—dishes that are simple, budget-friendly, and body-friendly. I’m thrilled to share the wisdom of Japanese nutrition with you. Let’s cook our way to a healthier life!