This Isn't Tuna. It's Tomatoes.
how one simple technique unlocks tomato's savory potential
If you’ve read my post Why I Never Order Spicy Tuna Rolls, you already know I have strong opinions about tuna. Like, the actual fish. I didn’t mince words when it came to that frozen, unrecognizable mystery mash that shows up in so many rolls. In response, I offered a bold, spicy, plant-based alternative made from carrots.
So it should come as no surprise that I also have strong opinions about what a plant-based tuna should be. Carrots, in my opinion, are hands down the perfect base for a spicy tuna alternative. Their texture and ability to hold flavor make them a natural fit. But what about when you want something without heat that still gives you a tuna-like depth?
In that case, you’ll want to use tomatoes.
I know a lot of people reach for watermelon here. And yes, the look can be convincingly tuna-like. But to me, the flavor doesn’t quite follow through. The sweetness often lingers, even when masked with aromatics like ginger and garlic. I’ve had versions that were “fine” on a rice bowl, but they didn’t always play well in places like Rainbow Sushi Rolls where I needed the flavor to be a little less in my face.
Tomatoes might not scream “tuna,” but with the right treatment, they just might surprise you. It’s easy to forget that tomatoes are naturally rich in umami—that elusive fifth taste often described as savory or “meaty,” and usually associated with ingredients like mushrooms, soy sauce, or miso. This built-in depth gives tomatoes a kind of magical head start, making them a deliciously ideal blank slate for sushi, sashimi, rice bowls, and more.
What Gives Tomatoes That “Tuna” Depth?
In the Tomato Tuna base recipe, naturally umami-rich tomatoes are marinated in even more umami: tamari for salty depth, kombu (sea kelp) for a clean, ocean-y note, and dried shiitake for earthy richness. The result is a layered, balanced flavor that’s subtle, savory, and surprisingly tuna-adjacent.
Simple & Satisfying
I enjoy making Tomato Tuna because it comes together with a handful of simple ingredients. Though the tomatoes do require a quick blanching before peeling, nothing about the method is difficult. You won’t need fancy tools, just a little patience. They’re ready after just 2 hours in the marinade, though if you can let them sit overnight, they’re even better.
The Tomato Tuna base recipe can be prepared a few days ahead, too. I like to have it on hand to make sashimi, sushi rolls, or nigiri, but it plays well beyond sushi. Think tomato tuna and avocado toast, savory grain bowls, or Japanese-inspired noodle dishes. Once you’ve got a batch ready, the ways to use it are nearly endless.
What Kind of Tomatoes?
Wondering what kind of tomatoes to use? Go for firm but ripe ones with good flavor and enough structure to hold their shape. Here are a few solid options:
Roma – Their elongated shape makes them ideal for nigiri and sashimi-style slices.
Heirloom – Packed with flavor, but go for firmer ones and steer clear of the extra juicy or overly soft varieties. You might need to get creative with the slicing, due to their sometimes irregular shapes.
Slicer tomatoes – Readily available and surprisingly effective. Just choose ones with good firmness, and you’re good to go.
How to Make & Use Tomato Tuna
The Tomato Tuna PDF includes the full recipe, plus four creative ways to use it. Here’s a peek at what’s inside:
Tomato Tuna (Base Recipe) Silky, savory, and subtly ocean-y. The tomatoes soak up a marinade of deep umami flavors, resulting in a bite that’s balanced and bright without trying too hard.
Maguro Don-Style Rice Bowl Comforting and craveable. Warm rice meets cool, marinated tomato tuna for a texture contrast that’s satisfying.
Tomato Tuna & Mango Tartare A spoonable starter that feels both fresh and indulgent.
Tomato Tuna Nigiri Sushi
Finished with a brush of ponzu and a sprinkle of scallions, ginger, or jalapeño, these offer a simple but delicious sushi bar–style bite at home.
Tomato Tuna Sashimi with Ponzu Butter I can never seem to make enough of this one. It’s a crowd pleasing favorite that feels gives sushi lounge vibes at home.
Ready to give Tomato Tuna a try?
Download the Bonus Edition PDF to get the full Tomato Tuna recipe, step-by-step instructions, and the recipes for ways to use it.
Fantastic post Marissa.
Amazing! 🌹