Georgian ethnographic museums will tell a lot about Ketsi. It is made out of two different materials as people of Guria cut them out of a stone, while mountainous villages of Imereti – Shrosha, Makatubani and Satsamleti create Ketsi with the oldest clay technology. Stone and clay pans differ in sizes and thermoregulation systems. Our ancestors used it for baking pastry. It evenly distributes heat on the whole surface and that's why Khachapuri made on Ketsi has a whole different taste.
After a while people started using Ketsi for preparing other dishes as well, the most significant among which is Shkmeruli.
For Shkmeruli you'll need a medium size chicken, 4 cloves of garlic, sour cream and salt. First roast the salted chicken and cut it in half. Do not throw away the oil you've roasted the chicken in, add some water-mixed sour cream and ground garlic to it instead. Place the mixture on Ketsi, bring it to simmer and pour down onto the chicken.