Combine all ingredients except the sesame seeds into a re-sealable plastic bag and marinate for 30 minutes.

Heat your grill to medium-high heat while you wait.

After 30 minutes remove the steaks and discard the remaining bag of marinade.

Sprinkle the 3 TBS of sesame seeds on a plate and roll the steaks around coating them evenly.

Using a pair of tongs wipe the grill grates with a paper towel that's had a few TBS of vegetable oil applied.

Grill steaks for 2-3 minutes per side being careful not to overcook the tuna or burn the seeds.

Remove the steaks, slice, and enjoy.