Tuna Burgers with Wasabi Mayonnaise

Tuna Burgers with Wasabi Mayonnaise
Makes 6 burgers

1 tablespoon unseasoned rice-wine vinegar
Pinch of sugar
1/4 cup extra-virgin olive oil
Coarse salt and freshly ground black pepper
1 pound sushi-grade tuna, very finely chopped
2 scallions, white and light green parts only, trimmed and minced
1 tablespoon soy sauce
1 tablespoon toasted sesame oil
1 teaspoon lemon zest
Canola oil, for cooking
1/2 bunch arugula
Wasabi Mayonnaise (recipe follows)

Place vinegar and sugar in small bowl. Slowly whisk in 2 tablespoons olive oil to form an emulsion; season with salt and pepper; set aside. Place tuna, scallions, soy, 2 tablespoons olive oil, sesame oil, and lemon zest in a large bowl; season with salt and pepper. Mix well, using your hands, to combine. Divide tuna mixture into six equal portions and form each portion into a 1/2-inch thick patty.

Place a large nonstick skillet over medium heat and add enough canola oil to coat bottom of skillet. Add patties, and cook until medium-rare, 2 to 3 minutes per side. Place arugula in a large bowl, drizzle with reserved dressing, and toss to combine. Divide arugula evenly between 6 plates. Place one patty on each bed of arugula; serve immediately with wasabi mayonnaise.

Wasabi Mayonnaise
Makes enough for 6 burgers

1 large egg, room temperature
2 teaspoons unseasoned rice-wine vinegar
1 tablespoon fresh lemon juice
1 teaspoon fresh lime juice
1 1-inch piece fresh ginger, peeled and grated
1 tablespoon wasabi paste
1/2 teaspoon soy sauce
3/4 cup canola oil
Coarse salt

In the bowl of a small food processor, combine egg, vinegar, lemon juice, lime juice, ginger, wasabi, and soy sauce; pulse to combine. With food processor running, slowly drizzle in canola oil until mixture is emulsified. Season with salt.