There's as much Mon and Burmese food as Thai at Sangkhlaburi's small but popular night market. Keep an eye out for Myanmar yam kôw soy, a noodle and tofu salad in a tomato-based sauce, served as spicy as you like it – despite the name, it's nothing like the famous kôw soy soup from northern Thailand.
To try some Burmese or Karen food, look for Ahahn Puen Mueang 7 Yang's red picture menu in the southeast corner of the market.