Dredge the fish fillets is flour and refrigerate for about 30 minutes. Melt the butter in a skillet with the olive oil until it is hot, but not smoking. Add the fish fillets and determine the total cooking time based on the fish thickness, -10 minutes of total baking time per inch of fish thickness. If the fish is 1/2 inch thick, the total cooking time is 5 minutes. If the fish is 1/4 inch thick, the total cooking time is 2 and 1/2 minutes. Turn the fillets halfway through the total cooking time and place a thin slice of lemon on top of each piece of fish, and sprinkle with parsley or paprika. Finish cooking and serve with lemon wedges and your choice of a side dish.