This place is at the government complex building B on Chaeng Wattana Soi 7. The Building that houses the Immigration Department and a ton of other Government offices.
There are two big food courts in Building B the one closer to immigration is the one you want. Look for the big yellow sign I know it says Vegetarian but it is completely Vegan 'Jay' (no meat, no fish, no eggs, no milk). One of the staff speaks English but as this is a basic food court style stall you can just point at the things you would like.
There are about 8-10 dishes to chose from, fresh hearty Thai food at about 50 baht for rice and three servings of food,(one serving is about one ladle of food). They usually have some veggie sausages/satay sticks and a few other side orders available as well.
I just thought I'd add this as immigration is in the middle of nowhere to let people know there is a Vegan option even if you are stuck having a long old day at the immigration department.
I know the people who run this place from way back when they owned UR Station. When immigration relocated they relocated too following their loyal customer base. The two owners/mangers are a very nice people they asked about how my job was going and how the new owner of UR Station was ticking along. Pleasant Surprise after a long day
Updated from previous review on Friday June 15, 2012
Cons: Miles away from anywhere