Heat the olive oil in a skillet over high heat. Upon placing the salmon skin-side down, make sure it lies flat, pressing it down if needed (gently). Lower the heat to medium and cook until the fish turns opaque about 3/4s pup from the bottom of the fillet (about 4-6 minutes). Wild salmon will take less time than farmed. Ideally, you want a medium-rare salmon fillet, but it is important to cook to your preferred doneness. Transfer the salmon to a place and let cool slightly while you make the sauce (tent with tin foil to keep warm).