Don’t throw that watermelon rind away! Use it to make these delicious and easy Vegan Spicy “Tuna” Sushi Stacks! Cubed watermelon rind is marinated overnight in a soy and sesame dressing, and then tossed with a spicy sriracha vegan mayo. Layered between seasoned sushi rice and an edamame-avocado spread, this savory take on everyone’s favorite hand roll will satisfy your persistent sushi craving, and prevent that watermelon rind from winding up in the trash.

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That’s TRASH!:

I love watermelon. It’s probably my favorite fruit in the world. However, every time I buy it, I feel guilty about the amount of waste that comes from it. I buy one, cut it open, eat all of the juicy red parts, and then throw away the rest. 

What else are you supposed to do with the rind besides toss it in the trash? 

They say that the best way to prevent food waste is to make sure that you’re eating everything that you buy. With watermelon, we’re buying 15 to 20 pounds of it at a time, and throwing away nearly half of that because we’ve been conditioned to only eat the sweet red part.

If that’s not food waste, then I don’t know what is.

What if there was a way to treat the less sweet, and, admittedly, less attractive white rind of the watermelon so that it was just as tasty and delicious as the red? What if by making the rind into something special, it would double the amount of food you could get from a single watermelon, and greatly reduce the amount of waste?

People have been pickling watermelon rind for probably about as long as people have been eating watermelon, but I didn’t personally grow up with folks who were that resourceful, so I apologize if the concept of eating the rind is so novel to me. Growing up, 100% of the times that I ate watermelon, I just threw the rind away.

As an adult, when I finally learned that pickled watermelon rind was a thing, and so I gave it a shot. Truth be told, I didn’t dislike it, but I honestly didn’t love it. The texture was great. The flavor was great. But I just didn’t really have an occasion to eat them. Snacking on pickled watermelon rind just didn’t do it for me. 

Watermelon “Tuna”?:

Watermelon, though not quite the “Meryl Streep” of the edible plant kingdom that cauliflower is, has been turned into a number of things over the past couple of years. Do you remember the watermelon “ham” that was making its way around the internet a few years ago? Yup. Really!

Around the same time, I remember seeing watermelon being used to make a vegan “tuna” poke. The watermelon was cubed, marinated, and then served over rice, or as a side dish in the same way that Hawaiian style tuna poke would be. 

Although I didn’t try it myself, I imagined that it would be good. The texture would be interesting, but the flavors, with soy sauce and sesame oil, seemed like they would work well with a watermelon who can surprisingly play with savory flavors pretty well. 

Knowing what watermelon could be, I decided to see if I could push the limits with it a bit more. I got the idea of using it to replace tomatoes in a number of dishes, and the result was really amazing. However, after using all of this watermelon in all of these delicious recipes, I was left with the nagging voice that I’m always left with when I eat watermelon, “You’re going to just thrown ALL of that rind away?!”

So, to appease that voice, I threw all of the rind in my fridge, instead of the trash, and I swore that I would so something with them one day.

The idea of watermelon “tuna” came back to me, and I thought about the idea of pickling watermelon rind, and I decided to weave those concepts together. What if I marinated the rind in a soy sauce and sesame oil mixture, and allowed the rind to soak up those flavors. I didn’t know what to expect since the rind isn’t as sweet as the flesh, but I decided to give it a shot anyway.

From the very first test, I knew that I was onto something. The watermelon flavor was not overpowering, if even recognizable at all. The texture was nothing like what you’d get from actual tuna, it was more like a cucumber, but I definitely preferred that fresh texture to a flesh texture. 

How does it stack up?

So, I had a bunch of deliciously marinated watermelon rind in my fridge, but what was I going to do with it? Folks have been asking for more sushi videos on my channel, so I though that maybe the watermelon rind could be used for something like that.

I looked up what sushi chefs normally use to make spicy tuna hand rolls, and it turns out that it’s pretty much just tuna and sriracha mayo.

Sold!

Admittedly I’m a sucker for a sriracha mayo, and anything adjacent to it, so I knew that’s the direction I wanted to go in. I also thought about switching up the structure of the sushi a bit, and I was reminded of the stack style sushi that Yard House sells. Of course they don’t have a vegan option, so I that gave me even more incentive to make one.

The result, a spicy “tuna” sushi stack that’s made with watermelon rind that would normally just be thrown out. This is literally a trash to treasure story, and I’m so grateful that I am the one who gets to tell it.

Below is a list of all of the ingredients you’ll need to make theseeasy Vegan Spicy “Tuna” Sushi Stacks, along with suggestions for substations or changes that can be made to the dish.

Here’s what you’ll need: (contains affiliate links)

  • watermelon rind – This recipe was created as a way to use the leftover rind from my Easy Watermelon Recipes video. In that video I also show y’all how I like to cut my watermelon to make those recipes. I have full written instructions in the recipe below, but basically, this recipe, which is for two sushi stacks uses about ⅛ of a watermelon’s rind. Don’t want to use the rind? Go ahead and just use the red flesh instead. 
  • Dulse granules – Dulse is a “red seaweed” that is used to season foods, and to add a bit of iodine to your diet if you’re not consuming iodized salt. I like it in this recipe because it adds a brininess to the watermelon rind, pulling it in that “tuna” direction. It doesn’t’ taste “fishy”, per se, but it does have the essence of the sea. You can leave it out if you don’t have it, or if you don’t really care to purchase an ingredient that you only need ⅛ of a teaspoon of.
  • Rice wine vinegar – Milder than white wine or apple cider vinegar, rice wine vinegar adds the perfect brightness to the watermelon rind without making things too pungent. You could use another vinegar in its place, but I would maybe dial it back a bit as to not overpower things. 
  • Bragg’s Liquid Aminos  – I don’t remember the last time I actually purchased “soy sauce”. At this point, I just prefer and I am just more familiar with the milder flavor of Bragg’s. So, anytime you see Bragg’s Liquid Aminos in one of my recipes, feel free to substitute-in whatever low-sodium soy sauce or tamari you have on hand. Just know that my recipes are not tested using a “full-sodium” soy sauce, so if you do want to use one in this recipe, you’ll have to adjust a bit for the increased salinity.
  • Sesame oil – The watermelon rind “tuna” sort of walks the line with a poke. The sesame oil is an integral part to making this dish work. You could use toasted, but you might want to use a little less. If you don’t have sesame oil, just add a similar amount of toasted sesame seeds to the mix. 
  • Vegan mayo – lately I’ve been using Best Foods (Hellman’s) vegan mayo because it’s fairly easy to find, and the most economical. Any vegan mayo will do, or you could make a batch of my Universal Cold Salad Dressing, and use it as a protein-rich alternative to the mayo in this recipe. 
  • Sriracha – I can handle quite a bit of heat, and I find that the sriracha in this recipe, as part of the sriracha mayo, adds more flavor than it does heat. Not a heat fan, reduce the amount. If you love a kick, then by all means, add a bit more.
  • Sweet chili sauce – I’ve started adding sweet chili sauce to my sriracha mayo recipes because it adds another layer of flavor. Don’t have it, just add a pinch of sugar to the sriracha mayo instead.
  • Short grain rice – This is my go-to rice, and it’s the best for making sushi. In a pinch, any rice will do, just make sure it’s a bit stickier so that the dish will still have some structural integrity. 
  • Seasoned rice wine sushi vinegar – This may seem a bit redundant because this recipe also calls for regular rice wine vinegar. Sushi vinegar is just rice wine vinegar with salt and sugar added. If you don’t have both, then just add a pinch of salt and sugar to the components of this dish that call for sushi vinegar. 
  • Avocado –  Choose a good, ripe avocado for this recipe. If you need to ripen-up your avocados, place them in a paper bag, and check them daily until they ripe. When they are perfectly ripe, you can place them in the fridge until you’re ready to use them. A perfectly ripe avocado will stay perfect for quite a few days if kept in the fridge. 
  • Shelled edamame – I always keep a bag of frozen shelled edamame on hand. Just pull them out of the freezer as you’re getting everything else ready, and they should be thawed by the time you are ready to eat. 
  • Nori – Since we are making a sushi stack, we need nori to help sell that sushi flavor. If you’re not a fan, then just leave it off. Love the stuff? Add a bunch more, or put it in between the layers, lasagne style. 
  • Black or toasted sesame seeds – For dishes like this, I really like the pop of black that the black sesame seeds add. Only have toasted, just use those. Only have white but they’re not toasted? Toss them in a dry pan until they smell toasty,and then remove them from the pan to cool.
  • Ponzu sauce – I’ve been really loving ponzu sauce lately because it’s got a bit of brightness along with its saltiness. Imagine soy sauce mixed with lemon juice… because that’s pretty much what it is.
  • 3.6” ring mold – I get that not everyone has a ring mold on hand. You could buy some for this dish, or get crafty and make one out of aluminum foil. If for some reason you have a tuna can on hand? You could use a very clean can with the top and bottom removed.

Easy Vegan Spicy “Tuna” Sushi Stack

Easy Vegan Spicy “Tuna” Sushi Stack
Prep Time
15 mins
Cook Time
20 mins
 

Turn the watermelon rind that you normally throw away into a delicious and Easy Vegan Spicy "Tuna" Sushi Stack, with all of the pizzazz of your favorite hand-roll, but without any of the actual tuna.

Course: Appetizer, Main Course, Snack, Sushi
Cuisine: Japanese, sushi
Servings: 2 stacks
Author: Michael Monson
Ingredients
  • 8 ounces watermelon rind (about 2 cups) skin removed, cut into ¼” to ½” cubes
  • teaspoon dulse granules
  • 2 teaspoons rice wine vinegar
  • 2 teaspoons Bragg’s Liquid Aminos or low sodium soy sauce
  • 1 teaspoon sesame oil
  • 2 tablespoons vegan mayo
  • 1 to 2 teaspoons sriracha
  • 1 teaspoon sweet chili sauce
  • 1 cup cooked short grain rice, cooled to room temperature
  • 1 tablespoon seasoned rice wine sushi vinegar (or 1 tablespoon of rice wine vinegar with a pinch of salt and sugar)
  • 1 ripe avocado
  • ¼ cup shelled edamame
  • 1 sheet nori
  • Black or toasted sesame seeds
  • Ponzu sauce or Bragg's Liquid Aminos (optional)
Instructions
To prepare the watermelon rind:
  1. To prepare the watermelon rind, cut your watermelon in half. With the cut sind on your cutting board, cut around the watermelon to remove any trace of the green skin. Cut the watermelon half into quarters, and then carefully cut the red flesh of the watermelon away from the white rind.
  2. Cut the rind into ¼ inch strips, and then cut those strips into cubes. Place the cubes into a bowl, and add dulse, rice wine vinegar, and Bragg’s Liquid Aminos. Toss to combine. Drizzle in the sesame oil, stir, and then cover and refrigerate for at least an hour, but overnight is best.
Prepare the remaining components:
  1. Combine vegan mayo, sriracha, and sweet chili sauce. Using a slotted spoon, or being careful not to add any liquid from the marinated rind, add the cubes of rind to the sriracha mayo. Stir together and set aside.
  2. Stir the sushi vinegar into the rice, and set aside.
  3. Casually mash the avocado with a splash of seasonal rice wine vinegar. Stir in the shelled edamame.
  4. Cut 1 inch thick strip from a sheet of nori. Cut that strip into “confetti”, or thin ribbons.
To assemble:
  1. Using a 3.6” ring mold, or circular mold of similar size, begin by packing half of the seasoned rice into the bottom. Top the rice with the ½ of the watermelon rind in mayo. If you’ve reached the top of your mold, gently move the mold up so that it’s still around the stack, but you now have room to fill the top. Fill the remaining space at the top of the mold with the avocado and edamame mixture. Using a knife or offset spatula. Smoothe the top of the avocado.
  2. Clean any spills on the plate, and then carefully remove the mold, sprinkle the top with sesame seeds, and nori “confetti”. Drizzle a bit of ponzu around the plate. Repeat with the second sushi stack, and serve immediately.
Recipe Notes
  • Not feeling the whole “stack” idea. Just use 2 sheets of nori, and make 2 sushi rolls using the same ingredients.
  • The watermelon rind “tuna” can also just be served over rice in the same way that one would eat a tuna poke.

easy vegan sushi recipe