Preheat the oven to 230°C.
Cut along one side of the spine to remove the backbone of the bird.
Flatten the bird by breaking the breast bone with your hand.
Cross the legs and tuck them into holes made in the skin.
Tuck the wings under the body and repeat for the second bird.
Marinade the birds in garlic, rosemary, lemon, and olive oil for one hour.
Grill skin-side down on a tray for three minutes under a hot grill.
Turn the birds and grill for 30 seconds.
Bake in the oven for eight minutes until the juices run clear.
Dissolve the stock cube in 180ml of boiling water mixed with olive oil.
Pour the liquid over the couscous and let it sit covered for five minutes.
Fluff with a fork and mix in the pepper, herbs, chilli, and lemon zest.
Serve the birds and meat juices on top of the couscous.