Heat oven to 180°C (350°F). Place salmon on a lightly oiled baking tray, sprinkle with salt and pepper and cover with foil. Cook for 8 to 10 minutes until fish is just firm outside, and still pink inside. Break up the salmon pieces with a fork, and mix with salt, pepper and parsley. Fold in most of the mashed potato, then continue adding it a spoonful at a time until you have a binding texture.