In a shallow bowl, mix together soy sauce, lime juice, wasabi paste, salt and pepper. Whisk until fully combined.
Evenly spread sesame seeds onto a plate or flat surface.
Heat olive oil and sesame oil in a skillet over medium-high heat.
When oil is heated, fully submerge tuna in soy sauce mixture and then coat all sides of the tuna in sesame seeds.
Gently place the sesame coated tuna in the skillet and cook to desired doneness. Depending on how thick the steaks are and how rare you like them, they should only need about 1 minute on each side. Remove from heat when cooked as desired.
We love to serve these steaks over a simply bed of spinach massaged with lime juice and olive oil!