An aromatic dish for small gatherings. These can be prepared on a sheet pan, but skillets make a better presentation. Preheat oven to 400. Rinse hen, pat dry, remove wing tips and backbone. Turn breast side up, open it up like a book, and whack it a time or two with your fist to crack the breastbone and flatten it out. Tuck the wings under the thighs. Oil the hen, season with salt and plenty of good black pepper. Line a well-oiled skillet with rosemary and garlic, place bird on top, and bake until browned.