Lately, I’ve covered the bottom of a skillet with a film of olive oil, heated it to medium high, then added a filet (have used salmon, black cod, halibut) skin side down for 2 or 3 minutes. Then stuck the skillet into a toaster-oven preheated to 450 (adding some thin pats of butter to the top of the fish). The top bronzes really well and the skin continues to crisp.
I generally use a filet of uneven thickness. This way my wife and daughter get “properly” cooked fish from the thin end and I get the close-to-raw center from the thick end that I like. You do have to watch the fish to avoid overcooking.
For spicing I often use a simple mix of salt and cayenne rubbed into the top of the fish (letting it sit for 15 mins or so before cooking).
