1. Place the chicken in a large zip-locking plastic bag. (You can also marinate the chicken in a dish; see Serving Suggestions at the end of this recipe).
2. In a bowl, whisk together the mayonnaise, garlic, oil and lemon juice (reserve the squeezed-out lemons).
3. Strip the rosemary and thyme leaves from their stalks, coarsely chop them, and mix them into the bowl. Season with plenty of black black pepper, but no salt yet.
4. Pour this mixture into the bag, add the squeezed-out lemon halves, then press out any air and seal. Gently massage the chicken through the bag so it is coated all over with the marinade.
5. Place in the fridge overnight, or for at least four hours, turning the bag now and then.
6. When you’re ready to braai the chicken, place a big double layer of heavy tin foil on the counter. Put the chicken in the middle and fold up and seal the edges to form a parcel. Reserve the bag containing the left-over marinade.
7. Gently cook the foil parcel over low braai coals for 25 minutes, turning it three or four times.
8. Open the parcel, remove the chicken, add salt to taste and place it directly on the braai grid. Braai over low coals for a further 25 - 35 minutes, or until the skin is crisp and golden, and the chicken is cooked right through. Baste the chicken often with the left-over marinade.
9. You can also roast the chicken in an oven. Pre-heat the oven to 180 °C, place the chicken on a baking sheet and roast for 45-55 minutes, or until cooked right through, basting now and then with the left-over marinade.