1. From the underside of the bird,run a knife along the side of each thigh bone,making a 1cm-deep incision either side of the bone to allow the marinade to seep in and ensure even cooking.
2. For the marinade,pound the bay and salt to a rough powder using a mortar and pestle,then add the fennel seeds and grind. Pound in the garlic,then stir in the oil to make a rough paste,leaving any garlic skins in it.
3. Rub the marinade all over the chicken,then season with pepper. Stand at room temperature to marinate for at least 1 hour.
4. Preheat a barbecue,ideally using coals,but gas will work,too.
5. Cook the chicken skin-side down over low,even coals (or on a medium heat) for 25 minutes,then turn over and cook for 20 minutes covered loosely with foil (to more evenly distribute the heat). Then move to a dish in a warm place,lightly cover and rest for 20 minutes before serving.
6. Meanwhile,grill the lettuce and lemon halves,cut side down,for 3 minutes. The lettuce will char and wilt slightly,but still hold its shape.
7. For the mayo,combine all the ingredients in a small bowl.
8. Dress the grilled lettuce with the balsamic and arrange on a serving plate with the rested chicken. Pour the chicken resting juices over the bird and the lettuce,sprinkle over the mint and serve with the charred lemon and mayo.
*Tip: I like to leave the skin on the garlic,which further intensifies a flavour that's already quite punchy,thanks to the bay leaves and fennel seeds.