Preparation Put oven rack in middle position and preheat oven to 500°F. Trim off and discard about 1/4 inch from top of garlic heads to expose cloves, then put heads on a sheet of foil. Spoon oil over garlic, then wrap up foil tightly to enclose. Roast garlic on oven rack until very soft, about 40 minutes. Meanwhile, season hens inside and out with 1 teaspoon salt and 1/4 teaspoon pepper. Tie legs together with string and tuck wing tips under. Transfer to roasting pan and roast alongside garlic until hens are golden brown and thermometer registers 170°F when inserted into leg joint, 30 to 40 minutes. Let stand, loosely covered with foil, 15 minutes. Unwrap garlic carefully and cool slightly, then squeeze pulp into a bowl. Add remaining ingredients (including salt and pepper plus 2 tablespoons pan juices from hens if desired) and stir until combined well. Halve hens lengthwise. Serve with aioli.
Preparation Put oven rack in middle position and preheat oven to 500°F. Trim off and discard about 1/4 inch from top of garlic heads to expose cloves, then put heads on a sheet of foil. Spoon oil over garlic, then wrap up foil tightly to enclose. Roast garlic on oven rack until very soft, about 40 minutes. Meanwhile, season hens inside and out with 1 teaspoon salt and 1/4 teaspoon pepper. Tie legs together with string and tuck wing tips under. Transfer to roasting pan and roast alongside garlic until hens are golden brown and thermometer registers 170°F when inserted into leg joint, 30 to 40 minutes. Let stand, loosely covered with foil, 15 minutes. Unwrap garlic carefully and cool slightly, then squeeze pulp into a bowl. Add remaining ingredients (including salt and pepper plus 2 tablespoons pan juices from hens if desired) and stir until combined well. Halve hens lengthwise. Serve with aioli.