Vegan Watermelon Tuna (Poke-Style)

This vegan watermelon tuna is the BEST plant-based substitute for raw tuna poke! It might sound a bit strange, but marinating and roasting watermelon gives it the perfect tuna flavor and texture! Use watermelon tuna in vegan sushi, vegan poké bowls, or just on its own!

Something that a lot of people find hard to give up when transitioning to a plant-based diet is fish, especially tuna or sushi-style fish. While there are some great Asian tofu sushi recipes, nothing quite replicates that tuna taste and texture like this watermelon tuna does!

The secret here is to marinate the watermelon and then ROAST it. Roasting the watermelon gives it this smooth, soft, tuna-like texture that is so good!

While it might sound like a strange use of watermelon, it's able to absorb all the savory flavors so well and when it roasts it becomes the perfect texture! Serve watermelon tuna with cilantro rice for a perfect poke bowl!

Why you'll love this watermelon tuna

• Plant-Based, Unprocessed - This recipe is made purely from fruit, so it is very unprocessed, low calorie, and a very healthy tuna alternative!
• Easy to Make - Making vegan tuna sounds difficult, but you only need to marinate watermelon, then roast it! This couldn't be easier!
• Savory, Delicious - When you make this recipe, you're going to find yourself not believing that it isn't real fish! This watermelon tuna could fool anyone!

What you need for this recipe

Ingredients and Substitutions:

• Watermelon - Plain, raw watermelon without seeds is the best! I used a whole mini watermelon, but any kind will work!
• Toasted Sesame Oil - This adds a slight nutty, but Asian-influenced flavor. Regular sesame oil will work as a substitute!
• Soy Sauce - Feel free to use low-sodium soy sauce, coconut aminos, or tamari for gluten-free options!
• Nori Flakes - Nori flakes are basically the flakes from dried seaweed, like you see on sushi rolls. You can usually find this in the Asian or International section of your grocery store. If you can find a seasoning called "nori furikake" that works wonderfully. If you can't find this seasoning, just omit it and add a little extra salt!
• Neutral Oil - I used canola oil but vegetable or even a light-bodied olive oil works as well.
• Lime Juice - If you can't get lime juice, fresh lemon juice will work.
• Rice Vinegar - Natural, unseasoned rice vinegar. However, if you have seasoned rice vinegar, that will work great! If you have neither, a white blasamic will do the trick. I do not recommend using apple cider or plain white vinegar.

How to Make Watermelon Tuna

Step 1: Prepare the Watermelon

First, use a sharp knife to cut off the ends of the watermelon. You can then stand it up on either end for easier cutting. Cut the whole watermelon in half if you'd like.

Carefully cut the rind off of the watermelon and discard rind pieces.

Then, chop the watermelon into roughly 1-inch pieces. Be aware that the pieces may shrink while cooking.

Lay the watermelon pieces out on a large plate, making sure they aren't on top of one another.

Sprinkle 1 teaspoon of kosher salt over the pieces and allow them to sit for at least 5 minutes. This will help remove excess moisture from the watermelon.

Step 2: Create the Vegan Tuna Marinade

While the watermelon is sitting, make the marinade.

To a bowl add the soy sauce, rice vinegar, toasted sesame oil, nori flakes, neutral oil, and lime juice and gently whisk together.

Once the watermelon cubes have sat for at least 5 minutes, pat them dry with a paper towel.

Add all the cubes to a sealable container or plastic sealable bag and cover with the marinade.

Seal the container and very gently shake to fully coat the cubes in the marinade.

Refrigerate for at least 2 hours, up to overnight.

Step 3: Roast the Watermelon

Pre-heat your oven to 350º Fahrenheit.

After it has marinated, place the entire container (NOT including the excess marinade) of watermelon onto an aluminum foil-lined baking sheet.

Spread the pieces out, making sure none are overlapping.

Roast in the oven for 50-60 minutes. Toss using a spatula halfway through roasting.

Step 4: Finishing Touches

After the 50-60 minutes, remove from the oven.

Scoop the pieces onto a plate and place in the fridge to chill for about 20 minutes, or until cool.

Serve this vegan watermelon tuna on rice, in salads, in sushi, or more. Garnish with scallions, sesame seed, and/or spicy mayonnaise.

Expert Tips

• If you dump the entire container including the marinade onto the foil-lined baking sheet, it will be fine. However, it increases the chances that the excess marinade will seep through and burn on the baking sheet. Save the excess marinade for a dipping sauce!
• Pair watermelon tuna with a simple spicy mayonnaise or a vegan yum yum sauce by mixing together vegan mayonnaise, rice vinegar, and sriracha! Stir and mix until it tastes how you like and drizzle on top!
• Make this a spicy vegan watermelon tuna poke by adding 1-2 teaspoons of red pepper flakes OR chili oil to the marinade.
• You can use pre-cubed watermelon to save you a few steps. However, make sure there are no black seeds in the cubes. Then, you may still want to cut them in half or you can marinade and roast for longer time.

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