Eggs.

You make the gypsy stand still against the tavern wall, arms and legs spread, making herself a perfect target, while you hand out eggs to all the assembled peasants and townsfolk. They leer and gawk at her shameful nudity while they form an orderly line in front of her, preparing to throw.

The first egg hits her right between the eyes. Yolk trickles down her nose and across her full, red, kissable lips while she sputters and fumes, unable to dodge or clean herself up. An auspicious beginning. The next hits the wall to her left, missing her completely. The third cracks against her left breast. Yolk drips off her coffee-dark nipple. The fourth also misses, but the fifth lands just above her navel. More yolk pools in her navel and drips down to collect in the thick, tangled bush of her pubic hair. Then the pelting begins in earnest.

Only when she's completely covered in egg, from head to toe, do you take her away from the wall and lead her back toward the centre of the street. You're not going to stop tormenting her, of course. Now that she's covered in egg-slime, she's in the perfect state to be put through her paces just a little bit more. What else could you have her do?