Pre-heat your oven to 200C (180C for fan assisted ovens) or Gas Mark 6.
Place the chicken into a roasting tin (preferably on top of lots of lovely root veggies) and untruss (cut the strings off) the bird.
Stuff the cavity of the bird with a lemon that has been cut into two halves, the garlic cloves and a handful of fresh rosemary and thyme.
Next, find where the skin has slightly pulled away from the breast meet (near where the cavity opens up) and run your hands underneath the skin, over the top of the bird. Do this gently so as not to tear the skin.
Stuff the pocket you've created with the butter mixed with the dried herbs.
Rub the skin with a little olive oil and liberally sprinkle with salt and pepper.
Cook for 25 minutes before turning the oven down to 170C (150C fan assisted) or Gas 3½ and cook for a further 40-55 minutes depending on size.
Once the bird is cooked through (see notes) leave to rest in the roasting tin for 15 minutes (the perfect amount of time to make your gravy) before serving.
Notes
Got a chicken that weighs more or less than 1.5kg? Cook it for 25 minutes for every 500g, plus an extra 30 minutes.