- 10 ounces sashimi-grade tuna, cut into 1-inch thick slices
- 1/4 cup light soy sauce
- ground black pepper to taste
- 1/4 cup light sour cream
- 1 tablespoon wasabi paste, or to taste
- 1 tablespoon peanut oil
- 4 flour tortillas
- 1 cup finely shredded cabbage
- 1/4 cup minced green onion
- Marinate tuna slices in soy sauce in a bowl, 10 to 15 minutes.
- Remove fish from soy sauce to a plate and season with black pepper; set aside.
- Whisk sour cream and wasabi paste together in a small bowl; cover and refrigerate until ready to use.
- Heat peanut oil in a heavy skillet over high heat. Sear tuna slices in hot oil until lightly browned, 15 to 20 seconds per side.
- Transfer rare tuna to a cutting board and cut into smaller pieces.
- Heat tortillas in a clean skillet over medium heat until warmed through, about 1 minute each.
- Serve tuna in warm tortillas topped with cabbage, green onion, and wasabi sour cream.