First, pat the fish dry with a paper towel. Remove as much moisture as possible to ensure you get a good sear in the pan. (Optional: Portion the fish into individual servings/filets)
Lightly season with pepper and salt.
Heat a very thin layer of avocado oil (or another cooking oil with high smoke point) in a non-stick skillet on medium-high.
Test the pan's readiness by dropping a few droplets of water in. It should sizzle upon impact. If it doesn't, give it more time, or consider increasing the heat level a bit.
Place the fish in the skillet skin side down. If skinless, choose either side.
Sear for 4-5 minutes, and then flip. On the seared side, you should see some crispiness and golden skin forming. This is your goal!
The second side will need less time, depending on thickness. Plan on 2-3 minutes before you begin to check
Start to test the doneness of the fish by using a fork to see if the flesh flakes easy. Once it does, remove from the skillet.
Using the same skillet, reduce heat to low and add wine. Scrape the bottom of the pan to remove any crusty bits left from searing the fish.
Bring to a simmer for 2-3 minutes and allow the wine to reduce by about 1/2.