The tuna for this recipe must be sashimi grade as only the edges will be thoroughly cooked. Sashimi-grade tuna is difficult to find unless you patronize a premium fishmonger or even better, a Japanese fish market, which typically carries it. (If you don’t have either in your area, ask at your local sushi bar if they would sell you sashimi tuna. I’ve bought fish that way.) To be sashimi grade, the tuna not only must be amazingly fresh, but it must be cut from the bottom of the loin, where there is no connective tissue. It should be free of any visible lines (no semicircles within the flesh) or blood, with even color. Its limited supply has made it very costly. The tuna for this filling is quickly seared, a technique known as tataki in Japanese cooking. With each mouthful, you enjoy the delicious contrast between the spicy-smoky seared crust of seasonings and the cool raw center of the tuna. Cucumbers add a nice crunch, as does a garnish of colorful sliced radishes.
Recipe information
Yield
makes 8 tacos
Ingredients
Preparation
Step 1
In a large bowl, mix together the red and chipotle chile powders, sea salt, cumin, coriander, oregano, and black pepper. Toss the tuna pieces in the seasoning mix.
Step 2
In a large, heavy, nonstick skillet, heat the vegetable oil on high heat. Sear the tuna pieces all around, 1 minute per side. Remove from the heat and slice the tuna into 1/4-inch-thick slices.
Step 3
In a bowl, mix the tuna with the cucumber, olive oil, sugar, lemon zest, and salt. Serve immediately. The filling will keep up to 2 hours in the refrigerator.
Step 4
To serve, place some shredded lettuce in each crispy shell, divide the filling equally between them, top with salsa and garnish, and arrange in a taco holder. Or, lean the filled shells in a row, propped upright, on a platter. Eat right away. To build your own, place some lettuce, then filling, in a crispy shell, top with salsa and garnish, and eat right away.
