Rinse bird, pat dry, remove wing tips and backbone with shears or a knife then turn the hen breast side up, open it up like a book and then whack it a time or two with the heel of your hand (you can use your fist if you like) to crack the breastbone and flatten it out.
Tuck the wings under the thighs. Oil the hen, season with salt and pepper. Place rosemary, garlic and whatever other herbs you might like in the bottom of a skillet, lay the bird on top, and pop onto the top rack of a hot oven (400) until legs wiggle.
