In a small bowl, whisk together the sesame oil, soy sauce, grated ginger, honey, and minced garlic to create a marinade.
Place the tuna steaks in a shallow dish and pour the marinade over them. Let marinate for at least 15 minutes at room temperature or up to 1 hour in the refrigerator.
Heat a non-stick skillet or grill pan over medium-high heat.
Remove the tuna from the marinade and season both sides with salt, pepper, and sesame seeds.
Add the tuna steaks to the hot skillet and sear for about 1-2 minutes on each side for medium-rare, or longer if desired.
Remove the tuna from the skillet and let it rest for a couple of minutes before slicing.
Garnish with sliced green onions and serve immediately.