Mike,
down on the River you'll find plenty of nice places that will, if not cater to your particular tastes, accomodate it. There is (was the last time I was down there, anyway) a couple of nice up-style yuppie restraunts right above downtown (and a good martini, too). I think it was St. Joesphine's. Close to the Modern art museum (pretty nice, really), made from the old Pearl brewery. Cool part of town, tho it is like a pile of spaghetti since all the highways meet there. Joesphine Ave. exit off of 281 (mcAlister).
You are missing out of the real fun, tho, sorry. Blanco Cafe (there are about 4 of them but the one on Blanco is the real deal). You can find guacomole stuff there, but it is real tex mex so not much else vegetarian. Very coarse, food not cusine. And one of the best hamburger joints is close by, but I won't even go there.
I dont' know anybody that still lives there, or otherwise I could tell you the hot spots so you don't seem like one of the bridge and tunnel tourists (that's what we in NYC used to call the kids from New Jersey). Sorry. Most of my other info is old. One of my favorite places used to be a chain called the Texas stores. One side was liquor, the other guns. Very authentic!
have fun, San Antonio is a great visit.
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