Sesame Crusted Tuna Tataki with Pickled Onions

What is tataki? Tataki is a Japanese-style preparation in which fish or meat is quickly seared on the outside, sliced, and served with a bright citrus-based sauce. Tuna tataki is especially delicious because the center stays tender while the outside develops a light, savory crust. This sesame seed tuna tataki salad with pickled onions is simple, fresh, and full of contrast: rich tuna, nutty sesame seeds, peppery arugula, tangy onions, and ponzu sauce.

This recipe was inspired by a recent East Coast trip that ended in Nantucket, where fresh seafood was everywhere. During the week, I enjoyed Maryland blue crabs with Old Bay seasoning, lump crab cakes, scallops, cod, soft shell crabs, lobster, fresh tuna, and even porgies that were caught locally and cooked within a couple of hours. That kind of seafood experience is a reminder that simple preparations are often the best, especially when the fish is fresh and flavorful.

Fishing with the locals.

Catching a porgy with help from Francisco.

Porgies dredged in seasoned flour.

Porgies fried simply in olive oil and butter.

This sesame seed tuna tataki with pickled onions uses a dry rub made from black sesame seeds, white sesame seeds, coarse sea salt, and coarsely ground black pepper. The tuna is seared briefly so the sesame crust becomes fragrant without overcooking the center. Pickled onions add crunch and acidity, while arugula gives the salad a fresh, peppery base. Serve the tuna tataki with ponzu sauce, a citrusy soy-based sauce that complements the fish beautifully.

Tips for Making Tuna Tataki with Pickled Onions

Tuna

For the best tuna tataki, buy tuna from a reputable fish vendor. Some fish markets sell defrosted tuna steaks, and that can be perfectly fine when handled properly. Look for tuna that is light pink or deep red, not brown or dull from oxidation. A darker strip of muscle in the steak is normal, but the flesh should look firm and should not be separating. Fresh tuna should also smell clean, not strongly fishy.

Choose tuna steaks that are about 1 to 1 1/2 inches thick, or approximately 3 to 4 cm. Thinner steaks cook very quickly, so the searing time must be short to keep the center rare. As a general guide, plan on about 1/3 pound of tuna per person when serving this as an appetizer or salad. If your fishmonger can cut a block-shaped piece of tuna, it works especially well because it is easier to coat, sear, and slice evenly.

Block-cut tuna is ideal for tataki.

Pickled Onions

Thinly sliced onions bring sharpness, texture, and brightness to this tuna tataki salad. Slice the onion as thinly as possible using a sharp knife or mandoline. Sprinkle the sliced onion with salt, then squeeze it gently with a gloved hand or inside a plastic bag. This helps soften the onion and draw out excess moisture. After squeezing, discard the onion juice and place the onions in a bowl. Add sugar and vinegar so the onions can absorb the flavor and lightly pickle while you prepare the tuna.

Sprinkle the thinly sliced onion with salt and squeeze to remove excess liquid.

Sliced onion ready for pickling.

Tuna Tataki Dry Rub

The dry rub for this sesame seed tuna tataki is simple but flavorful. Combine white sesame seeds, black sesame seeds, coarse salt, and coarsely ground black pepper in a shallow bowl or flat container. The sesame seeds give the tuna a nutty crust, while the pepper and salt season the outside of the fish.

Sesame seed dry rub for tuna tataki.

Pat the tuna dry, leaving just enough surface moisture for the sesame mixture to cling. Press the tuna into the dry rub and coat all sides evenly. A complete coating gives the finished tuna tataki a better texture and appearance.

Coating the tuna with the sesame seed mixture.

Make sure every side of the tuna is completely coated.

Searing

Heat a cast-iron skillet until very hot, then add a small amount of cooking oil to prevent sticking. Sear the sesame-crusted tuna briefly on each side. The goal is to cook only the outside while keeping the center rare. Watch carefully so the sesame seeds toast but do not burn.

Searing the tuna in a hot skillet.

Plating Sesame Seed Tuna Tataki Salad with Pickled Onions

Allow the seared tuna to cool slightly before slicing. Arrange arugula on a serving plate and scatter the pickled onions over the greens. Slice the tuna into pieces a little less than 1/2 inch thick, or about 1 cm. Place the sliced tuna over the salad and drizzle with ponzu sauce, or serve the ponzu on the side so each person can add as much as they like.

Arugula with pickled onions.

This tuna tataki salad is light enough for an appetizer but satisfying enough to serve as a small main dish. The combination of seared tuna, sesame crust, tangy onions, fresh greens, and ponzu sauce makes it a clean and flavorful seafood recipe.

Sesame seed tuna tataki served with fresh greens and ponzu.