Position a rack in the middle of the oven and preheat the oven to 400°F.
Line a baking tray / sheet with a large piece of foil and place the salmon fillet, skin side down, on the baking sheet; set aside.
Mix together the breadcrumbs, Parmesan cheese, parsley and garlic in a small bowl.
Pour in the melted butter; season with 3/4 teaspoon salt and 1/3 teaspoon pepper (or to taste).
Using your hands (it's easier than using a wooden spoon), mix the ingredients together until the breadcrumbs absorb the butter (about 40 seconds).
Pour the mixture over the salmon, pressing it into the top until the fillet is completely covered.
Bake uncovered for 12-15 minutes (depending on the thickness of your fillet), until the crust is golden and the salmon is cooked and flakes easily with fork.
Serve with lemon wedges and a squeeze of lemon (optional).