
Possibly the best thing to do with a fresh cut of tuna- make Ahi Katsu! Beautiful red tuna wrapped in nori seaweed and coated in crispy panko crumbs, fried up short and fast, and served with the best homemade sauces in the world.
This recipe first appeared in Whisk by Ami Magazine. Photographed by Malky Levine.
This stunning kauai-lunch inspired dish somehow manages to be as delicious to eat as it is to look at. Serve this dish on a bed of micro greens(for that perfect restaurant look with no work at all!), and be ready to bask in the compliments. For another beautiful appetizer, I suggest Ahi Poké Wontons.
Ahi Katsu is sliced for the perfect stackable bites, and each piece is crunchy, with a beautiful raw centre, drizzled with wasabi aioli for a kick, and sweet unagi sauce.

What is Ahi Katsu
Ahi Katsu is a famous lunch food served in the Hawaiian islands. While it is pretty enough to be served as a fancy dinner appetizer, the locals eat it for lunch with a lightly dressed side salad. Lunch food in Hawaii(specifically, Kauai, where I grew up), is beyond. It can pretty hard to choose between Chicken Katsu, Kalbi Ribs, and Huli Huli Chicken, but we all know the real treat on the islands is fresh fish.
Which fish is best?
I recommend making this dish with raw ahi in the center. If you want a cooked Ahi dish, try Poké Bake!
For this, you want to make sure to get the freshest tuna available. If possible, ask your fishmonger(the dude you buy fish from) for the freshest fillet- simple. If you’re going at it alone, look for the reddest-pink meat(depending on the fish- bluefin, yellowfin, bigeye, or albacore) with an almost translucent sheen. The fish should not be brown. It should not look wet or weepy. You want a firm piece. We will cut it into two blocks.

Fried Ahi Katsu
After slicing the fish into two logs/long blocks, it will be prepped, fried, sliced, and served immediately. So make your side sauces first so everything is ready to serve right away!
First, we’ll wrap the tuna in a piece of nori- I simply cut it to the right side and then whet the edge so it sticks to each other.
We’ll make a quick and easy tempura batter to dip the nori wrapped ahi in, and then coat the whole block in panko crumbs. Make sure to use Japanese white panko and not golden breadcrumbs, which are definitely not as crunchy.
Heat up oil in a shallow pan and fry each log for only 30 seconds. If you fry it any longer the centre will be cooked through. I found half a minute to be just perfect to crisp the tempura but still leave the ahi raw.

Homemade Island Sauces
These two sauces take this Katsu to the next level! And I promise they are so simple to make.
Wasabi Aioli- This tangy sauce gives just the right spicy kick without being overwhelming. All you need is a small drizzle(or more if you like spice).
Unagi Sauce– Basically an upscale homemade version of teriyaki sauce. This stuff is seriously goooood! You only need 3 ingredients: soy sauce, Mirin, and sugar, but the combo is intoxicating. I suggest doubling the recipe and keeping this sauce on hand in the fridge for sushi salads and marinating salmon.
Serving Tips
- After the Katsu logs are fried and crispy, let them drain for a half a minute on a paper towel and transfer to a cutting board. Slice into 10 pieces- this is easiest to do with a serrated knife!
- For a really pretty presentation, arrange some micro greens on a small wooden or ceramic platter and lay the slices on top, leaning each one on the next to the centers are facing up. Finish with a drizzle of unagi sauce, and then wasabi aioli, and enjoy!!
TWO HAWAIIAN DESSERTS TO FINISH YOUR MEAL


The flavors of the islands really come together in this delicious dish- enjoy as an amazing lunch, or serve as an appetizer- called a pupu (pooh-pooh) in Hawaiian. If you try it, Please leave a review and share your favorite food pics with me on Instagram.
Happy cooking, Estee

Ahi Katsu
Ingredients
Ahi Katsu
- 1 ½- 2 lbs fresh sashimi-grade ahi cut into 2 blocks, 1 ½ in. by 1 in., about 6 inches long
- 2 sheets of nori seaweed
- ½ cup flour
- 1 Tbsp cornstarch
- 1 egg
- 2-4 Tbsp water
- ½ tsp salt
- Grind of black pepper
- 1 ½ cup panko crumbs
- Vegetable oil for deep frying
- Microgreens for serving
Wasabi Aioli
- 1/4 cup mayonaisse
- 3 tsp dry wasabi powder
- 2 1/2 tsp lime juice
- 1 garlic clove, crushed
- 1 tsp water
Unagi Sauce
- 1/4 cup soy sauce
- 1/4 cup mirin(japanese rice wine)
- 1/8 cup sugar
Instructions
Ahi Katsu
- First prep both sauces and set aside.
- In a large bowl, whisk together flour, cornstarch, and egg. Add 2 Tbsp water and whisk to combine. Add more water 1 Tbsp at a time until the batter is workable and there are no clumps left. Season with salt and pepper.
- In a wok or deep pot, heat oil to 375 f, or until the oil is shimmering.
- Wrap each piece of ahi lengthwise in a piece of nori seaweed. Measure the ahi against the seaweed first. The edges should match up- if the seaweed is too long, cut it to size with kitchen shears or a sharp knife.
- Once you have wrapped the ahi, dip your fingers in water and run the water on the edge of the nori, then continue rolling it to stick the edges together.
- Dip each ahi block wrapped in nori first in the tempura batter, making sure to coat the whole thing, including the ends, and then in the panko crumbs. Add to the hot oil immediately. Fry the fish till it is golden brown, only 30 seconds each, for a raw centre. Personally, I think this is the prettiest and most delicious way to eat Katsu, but if you want the fish to be fully cooked in the centre, fry it for a minute to a minute and a half.
- Transfer the katsu to a cutting board and slice each block into about 10 pieces, each ¼ inch thick.
- Sprinkle microgreens on a wooden platter(or a leaf like in the photo!), and arrange the katsu slices leaning on each other in a row, centres exposed.
- Drizzle with unagi sauce, and then wasabi aioli. TIP: Place sauce in the corner of a small ziplock bag. Snip off the end when you are ready to use and you will get the perfet thin drizzle! Enjoy hot.
Wasabi Aioli
- Add all ingredients to a hand blender and blend until smooth.
Unagi Sauce
- Add soy suace, mirin, and sugar to a saucepan and bring to a boil. Lower the heat and simmer for 5-7 minutes, stirrng occasionally, until the sugar has dissolved and the sauce has thickened just slightly. Keep a careful watch that it doesn't over cook- it will thicken more as it cools. Let cool and transfer to a storing container in the fridge, or place in a squeeze bottle.
WOW!! So ono!! Former Kealia boy here now living in Boulder City NV missing the “local grinds” from the ‘aina, good thing for the internet!! I can look up recipes and have the taste of home here. Mahalo!!