Salt and pepper the salmon. Sprinkle a little flour on one side and pat it in gently.
Heat clarified butter over medium-high heat. Add the salmon, flour side down, and let sear for 2 1/2 minutes. Flip and sear the other side for ~2 more minutes. The salmon should be underdone at this stage, b/c it will cook in the sauce (as well as continuing to cook after you remove it from the pan.)
Add the capers and squish some to release briney flavor. Add lemon juice and wine and reduce by about half. Add the butter.
When the butter is almost melted, return the salmon and its juices to the pan. Mix the pan sauce and spoon over the salmon.
Sprinkle parsley if using.
If using an instant read thermometer, the target is 145*F.
Salmon isn't nearly as good if overcooked, so be careful not to wait too long to pull it out.