Cold Chicken with Lemon Sauce

• 4 lb (1.8 kg) oven-ready chicken
• 1 medium-sized onion

Wipe the chicken and remove the giblets. Place in a deep pan with salted cold water to cover. Peel the onion and add to the pan along with the peppercorns and bay leaf. Cover with a pan lid and cook gently for 40 minutes until tender. Allow to cool in the liquid for several hours or overnight so chicken flesh remains moist.

Skim fat from chicken stock and measure