1. Pat the fish dry with paper towel as much as possible.
2. Gently score 3 diagonal slices on the skin.
3. Sprinkle flake salt on both sides.
4. Put a non-stick pan on medium-high heat, warm the oil until hot but not smoking.
5. Add the fish skin side down.
6. Cook for a few minutes, as flesh starts to turn opaque, tilt the pan. Using a spoon, baste the top of fish with the oil from the bottom.
7. Just before fish looks fully cooked, add butter. Swirl around pan to melt, then continue basting the top of the fish.
8. Using a flat flipper, fish should be able to lift from the pan as the skin is cooked and crispy. Gently edge away from pan without tearing skin.
9. Add 2-3 tbsp vermouth and continue to baste fish until alcohol cooks off and pan begins to look dry again (but not burnt!) This happens quickly.
10. Remove from heat then squirt each fish with a little lemon. Voila!