Back when I was in high school, a friend of mine from an observant Jewish family told me that her family often ate in vegetarian restaurants. She explained that most of the Jewish dietary laws related to meat. If you ate in a restaurant that never served any meat products, you would automatically be observing most of the rules.
The exception, of course, is Passover. During Passover, Jews aren’t supposed to eat yeast-raised bread. This rule doesn’t just apply to wheat. It applies to four other grains as well: barley, rye, spelt, and oats. If any of these grains is allowed to sit in water for longer than 18 minutes, it becomes chometz. It’s against Jewish dietary law to eat, own, or benefit from chometz at any time during Passover.
Of course, people with celiac disease can’t eat wheat, barley, rye, or spelt—even if they haven’t become chometz—at any time of year. In other words, products that are gluten-free and don’t contain oats are automatically never chometz.
Ashkenazi Jews are also supposed to refrain from eating kitniyot during Passover. Kitniyot consists of grains and pulses (such as corn, rice, beans, lentils, peas, and possibly peanuts) that could be confused with chometz. Still, a gluten-free vegan cookbook would be a good place to look for good recipes to use during Passover. Lots of those recipes are accidentally Kosher for Passover!
Photo by Center for Jewish History, NYC