Spicy "Tuna" Maki
Spicy “Tuna” Maki

Do You Love Sushi? Try My Watermelon “Tuna” Maki

If you follow my instagram, you have probably noticed that I have taught popular sushi classes for many years. In fact, sushi is one of my great loves, and I respect the traditions. I also can’t stop myself from occasionally making a completely untraditional riff on sushi. So it’s out of love that I took a popular roll, the Spicy Tuna Roll, and made a plant based version. Instead of fish, I made watermelon tuna.

Whaaaaa? Watermelon TUNA?

Yes, watermelon is more than a refreshing summery snack. The open cells of the deep red flesh are full of juice, and when we eat it raw, it has a bit of crunch. But when you marinate it in savory liquids bake the flesh on low heat, it shrinks, becomes denser, and soaks up some of the marinade. That makes it a perfect “faux” to mimic the soft, raw tuna that is so popular in sushi bars.


Watermelon tuna is easy to make, it just needs some marinating time and an hour in the oven, so you do need to plan ahead. Because tuna is not sweet, this is the one time when a less sweet, less ripe watermelon is the better choice. So when you cut into a watermelon and it’s disappointing, it might be time to make watermelon tuna.

Or make Beet and Watermelon Juice!

Watermelon Tuna is great on bowls, too

Once I started making watermelon tuna for these sushi rolls, I usually had some left over. It was such a fun ingredient to have in the refrigerator that I now make extra just to have around. Any grain bowl would be a perfect spot for this juicy, sweet-and-savory treat. Use it for a Poke bowl, or just pile some leftover rice in a bowl and cover it with “tuna,” cucumber, sprouts, greens…you get the picture. An Asian vinaigrette or Tahini sauce goes well with it.

Spicy "Tuna" Maki
Spicy “Tuna” Maki

If you are making a salad, go ahead and top it with watermelon tuna, it’s lovely.

Clean, sustainable watermelon is a food that you can feel good about eating. So leave the tuna alone and make watermelon tuna!

Spicy “Tuna” Maki

Course Appetizer
Keyword plant based fish, plant based sushi
Servings 4
Author Robin Asbell


  • 4 cups 1/2 inch wide watermelon strips about 1/4 small seedless red melon
  • 1 tablespoon avocado oil
  • 1 tablespoon rice vinegar
  • 1 tablespoon tamari
  • 1 tablespoon hot oil or more
  • Roll
  • 2 cups sushi rice
  • 2 1/2 cups water
  • 2 tablespoons rice vinegar
  • 2 teaspoons sugar
  • 6 nori sheets
  • 12 slices cucumber peeled and seeded
  • chives or long sprouts
  • squash blossoms or shiso leaves
  • wasabi, pickled ginger, soy sauce


  • Place the watermelon strips in a zip top bag or a square tub. In a cup, stir the avocado oil, vinegar, tamari and hot oil. Pour over the melon slices and gently turn to coat. Marinate in the refrigerator for 6 hours or overnight.
    Preheat the oven to 350 F. Line a sheet pan with parchment. Lift the melon slices out of the marinade and place on the parchment.
    Bake for an hour, until shrunken and soft. Cool completely and chill.
    Rice: Wash rice repeatedly until water runs clear. Use a rice steamer if you have one, following instructions for your cooker. To cook on the stove, bring 2 1/4 cups water and the washed rice to a boil, cover tightly and lower heat to lowest setting. Simmer, covered, for 10-15 minutes, until all the water is absorbed. Let stand, covered, for at least 10 minutes. Meanwhile, heat vinegar, sugar and salt together in a small saucepan to dissolve. Pour over rice and fold in with a rice paddle. Fan rice to cool.
  • Fillings: Prepare the cucumber, slicing in very thin strips, and assemble your fillings.
    Prep your area. Prepare a bowl of cool water with a shot of rice vinegar added, and have a clean towel for your fingers. On each nori sheet, place about 3/4 cup of rice on the bottom. With wet fingers, pat the rice to cover all but the top 3/4 inch of the nori, leaving the remaining portion exposed. Spread a small dab of wasabi, and put a line of watermelon, and a slice of cucumber. Put sprouts in so the leaves hang out at both ends. Roll. Dab some vinegar water on the exposed nori and dry your fingers. Let rest, seam side down, for a minute. Slice. Serve with pickled ginger and soy sauce for dipping.