Roast salmon fillets with watercress sauce

Salmon fillets Heat oven to 200C/180C fan/gas 6. Line the bottom of a roasting tin with baking parchment. Brush 1⁄2 tbsp oil over the salmon skin and season. Place skin-side down in the tin and roast for about 15 mins until the salmon is just cooked through. Watercress sauce 2 tbsp vegetable oil 2 small…