Shared from Melina Hammer's cookbook Kid Chef
This is my favorite way to eat fish, because the preparation requires minimal work and produces perfectly cooked fillets each time. Once you get the hang of handling the spoon to baste in tandem with tilting the pan, this will no doubt become your favorite, too.
Pat salmon dry with absorbent paper and season on both sides with salt and pepper. Heat a large cast iron skillet over high heat. When the pan is hot, add the oil. Place the fillets skin-side down away from you into the pan, so if any spattering happens, there is less risk of being burned. Lower heat to medium and let sizzle until fish is caramelized and becoming opaque around edges, about 2 minutes.
Carefully turn fillets to second side and add butter and optional herbs to pan. Tilt pan slightly to pool melted butter on one side. Use a spoon to baste the fish with melted butter. Baste fillets repeatedly, until they are golden all over and cooked through, 1 minute or so, depending on the thickness of your fish.
Serve immediately with optional chopped parsley and lemon wedges.