Picazzo's has a fantastic GLUTEN FREE menu. The staff are all very knowledgeable and go out of their way to accommodate people with food issues.
Many people that I know with Celiac/GI try to avoid going during peak hours to avoid contamination, so I've always had great service and limited to no wait time and my food has been fantastic every time I've been there.
It is a bit pricey for pizza, but it's so nice to be able to eat out safely.
Would love to open a location in Austin as I don't live in AZ anymore, but whenever I'm there, I always make a trip.