Crush the garlic over softened butter and stir until garlic is thoroughly combined.
Then, either smear the mixture on a tuna steak and wrap it in foil (this gives you the most flavor, but less pretty) OR melt the butter/garlic mixture and brush it on the tuna steak.
Then put the steaks on a medium-hot grill (preheat it for a good ten minutes) and let cook 2-4 minutes per side or just until you’re happy with it.
Sprinkle with coarse sea salt.
Optional: Slice thinly and place on a bed of rice (or Tapai) and garnish with thinly sliced green onion.