I’ve made the Watermelon Tuna multiple times in the past few weeks, but every time I do, it still blows my mind. These oven roasted, soy-marinated watermelons achieve a total change in texture and taste, making them a good substitute for tuna. Get seated, It’s time for some plant-based omakase!
Let’s get straight into what kind of magic I’ve done to the watermelon to transform them into tuna. The process involves three main steps: 1) Marinate. 2) Roast. 3) Marinate.
Okay, that’s only three words. But if you really took your time, you can do this for a few days, especially the marinating part (granted, the more you marinate, the more tender & flavorful your watermelon will become!). The initial marinade consists of soy sauce, sesame oil, mirin, and seaweed flakes — it’s meant to help you infuse all those familiar umami and briny flavors into the watermelon.
Yep, you read that right. We’re roasting the watermelon to give it that slightly squishy yet firm tuna texture. The roast is a very slow one — the low temperature will slowly tenderize the watermelon without charring or caramelizing it, so as to retain that raw look.
The final marinade is a brief but important one. After a couple of trials, I realized that when you place the hot watermelon (after roasting) back into the cold marinade, you not only allow the watermelon to cool down quicker, but allow the watermelon to re-absorb all that umami flavor from the marinade.