Indoor fish

Cooked a fresh .75lb tuna steak Tuesday. What was unusual about this is I did it indoors, and not on my BBQ. I used a frying pan on the stove burner, on high. Nothing in the pan. Cooked it for 5 minutes, 2.5 per side. Middle was still red, outside was white. I'm still alive, so I may have done it right, or I just ate warm sushi.