1. Using kitchen shears and working with 1 hen at a time, with hen breast side down, cut through bones on either side of backbone; discard backbone. Flatten hens and lay them breast side up on counter. Using sharp chefs knife, cut through center of breast to make 2 halves.

2. Using your fingers, carefully separate skin from breasts and thighs. Using metal skewer or tip of paring knife, poke 10 to 15 holes in fat deposits on top of breasts and thighs. Tuck wingtips underneath hens. Pat hens dry with paper towels.

3. Combine 2 tablespoons salt, thyme, marjoram, and rosemary in bowl. Sprinkle half of salt-herb mixture on underside (bone side) of hens. Add oil to remaining salt-herb mixture and stir until mixture is evenly coated with oil. Add baking powder and stir until well combined. Turn hens skin side up and rub salt-baking powder mixture evenly over surface. Arrange hens skin side up and in single layer on large platter or plates and refrigerate, uncovered, for at least 4 hours or up to 24 hours.

4. Adjust oven racks to upper-middle and lower positions, place rimmed baking sheet on lower rack, and heat oven to 500°F.

5. Once oven is fully heated, spray skin side of hens with oil spray and season with pepper. Carefully transfer hens, skin side down, to preheated sheet and cook for 10 minutes.

6. Remove hens from oven and heat broiler. Flip hens skin side up. Transfer sheet to upper rack and broil until well browned and breasts register 160°F and drumsticks/thighs register 175°F, about 5 minutes, rotating sheet as needed to promote even browning. Transfer to platter or individual plates and serve.

Serves 4