Preheat the oven to 170°C
Place the garlic head in a baking tray, drizzle with olive oil and cover the tray tightly with foil. Roast for 50 minutes to 1 hour till tender (do check in between).
Allow the roasted garlic to cool lightly and then squeeze out from the skins into a bowl.
Using a fork, mash the roasted garlic well to form a coarse paste. To this add the shallots, lemon juice, balsamic vinegar, rosemary and mix well to combine.
Place the lamb chops in this marinade and season with salt and pepper. Keep for at least 2 hours before grilling.
Preheat the oven to 180°C if using both the pan and oven method.
Heat a grill pan to high and season with oil. Grill the lamb chops (in batches) on either side for 1 minute and then transfer to an oven proof baking tray.
Cook in the oven for another 1 minute for juicy and succulent chops with a blush of pink inside. If using only the pan method, cook the lamb chops for 1 ½ -2 minutes one either side.
Rest the lamb for 5 minutes before serving.