Preheat oven to 450°F and line a rimmed baking sheet with a silicone liner, parchment, or foil. Arrange salmon fillets on the prepared baking sheet, skin-side-down.
In a small bowl, add the marinade ingredients: parsley, garlic, oil, lemon juice, Dijon mustard, salt and pepper. Stir to combine.
Generously spread the marinade, brushing over the top and sides of the salmon then top each piece with a slice of lemon.*
Bake uncovered at 450°F for 12-15 min or until just cooked through, flaky,
and the salmon reaches an internal temperature of 145˚F at the thickest portion on an instant-read thermometer. Do not over-cook.