When I was walking around the city centre of Yangon I encountered many small shops preparing and selling kun-ya.
Kun-ya is a a combination of chewing betel leaves with areca nuts (betel nuts) and slaked lime paste (calcium hydroxide). The recipe of what is inside the betel leaf is different from shop to shop, with some also including tobacco, chili or other ingredients. After chewing it is either spat out or swallowed.