Chiang Mai is famous for its Thai noodles cooked in various broths ranging from mild to can't-handle-it-the-next-morning spicy. Non-vegetarians should try the Kho Sui or the Egg Noodle Curry and the Sai Oua made from pork sausages. Be sure to try the vegetarian friendly red/green chilli dip available at local stalls.
There are only a handful of Indian restaurants in Chiang Mai, the most famous ones being Rajdarbar Indian Restaurant and New Delhi Indian Restaurant. The Whole Earth is a restaurant which serves specifically Indian and Thai vegetarian food, which is not easily available elsewhere. There are no famous Jain restaurants in Chiang Mai though it may be possible to find a hole-in-the-wall family run eatery somewhere in the local markets. Jains are advised to ask vegetarian restaurants to prepare their dishes as per their specific requirements.