Preheat the oven to 425˚F. Place the butter in an 8 x 11-inch baking dish and set in the oven for 5 minutes, until the butter is melted.
Remove the dish from the oven, add the parsley, oregano, garlic and pepper, and toss to combine. Carefully place the salmon fillets in the dish, and use a brush to spread the butter herbed mixture on top of the salmon.
Roast for 8-10 minutes, or until the salmon is cooked to your desired doneness.
Spoon any remaining butter sauce over the salmon and serve with more fresh parsley and lemon slices.