Rankin has a few buildings of historic and/or architectural interest. I have no information about this restaurant but I don't think it catered to vegetarians.
The Rankin Library is a nice place to stop and catch up with the latest on VT and post tips of your trip. Another nice things about libraries is the people working there are usually very knowledgeable about the area and little known attractions.
Rankin has a nice museum located in the restored Yates Hotel which was built by rich oil tycoon Ira Yates in 1927. The museum has a number of displays of the old hotel along with pioneer artifacts, a restored 1940 Ford fire truck, and a meteorite that is believed to be a fragment of the much larger one that hit near Odessa. Hours are 2 PM to 5 PM Thursday and Friday and 1 PM to 5 PM on Saturday.