If you are in Xi'an and want an alternative to the endless bowls of rice and noodles you have been consuming head over to Delhi Darbar. This authentic Indian restaurant is delicious and vegan friendly (their cashew cream sauce is actually cashew cream, not cashews and milk!).
When we were there a tour group of Indians came in. They had prearranged a buffet and seemed very happy with the food, which just goes to show you how tasty and traditional it is.
English menu, some English speaking staff.