A reusable core for polymer clay bodies!
It has one of those wooden doll knob things inside, the wooden ball at the bottom, and there's a hole across the top for the arms.
Wrap the core in foil, apply skin, score along the sides, bake, split and remove skin, stick together with clay and bake again disguising it as a shirt seam. The tummy ball is on the bottom so he can bend and look like his shirt is still tucked in.