Preheat the oven to 350°F (180°C). Leaving the skin intact on each clove, gather the cloves together into a bunch and wrap with aluminum foil, adding the oil, thyme, and salt before sealing the packet.

Cook in the oven for 30 minutes (you may want to agitate the bunch a few times during cooking to ward off uneven roasting, i.e., brown spots). Set aside and allow to cool before popping the garlic cloves from their skins.