Pat dry 2 tuna steaks (6-8 ounces each) and season with salt and black pepper.
In a shallow dish, mix 2 tbsp soy sauce, 1 tbsp sesame oil, and 2 minced garlic cloves for the marinade.
Coat the tuna steaks in the marinade, let sit for 15-30 minutes in the fridge.
Heat 2 tbsp olive oil in a skillet over medium-high heat until shimmering.
Remove the tuna from the marinade, allowing excess to drip off.
Sear the tuna steaks for 1-2 minutes per side for rare to medium-rare doneness.
Optionally, sprinkle sesame seeds over the tuna during the last minute of cooking.
Rest the tuna steaks for a few minutes on a cutting board.
Slice the tuna against the grain into thin pieces.
Serve the seared tuna slices with optional lime wedges and preferred sides.