It's well worth the walk from Nevsky to find this excellent little restaurant. The friendly and patient staff, although not English speakers, are used to helping foreigners navigate the exotic menu. The food is mostly classic Georgian (grilled meat, khachapuri cheese bread, and rich vegetable stews), but with several Azerbaijani dishes as well, including the excellent govurma (veal or chicken, dried fruits and herbs baked under a cheese and dough topping). Good quality ingredients and generous portions are guaranteed, although the output of the kitchen varies considerably (from good to very good) depending on who is working.
Next door to the main restaurant, which is often used for private celebrations, there is a more simply decorated cafe offering the same menu in less formal surroundings. Prices at both establishments are very reasonable.
