I've always liked that I can go to Carl's Jr. and order a low-carb burger (it's an option on their menu). It takes the hassle out of having to explain that when I say "no bun" I actually mean NO BUN.
here, click on the "Gluten Sensitive" button on the bottom right, and the link to the printable coupon will be at the bottom of that window.
Check out the full Carl's Jr. menu to know what else contains gluten and other allergens. This list will show every ingredient (unfortunately, their chicken has gluten in it even if it's not breaded).
It turns out there are actually fewer options at Carl's Jr. than I originally thought (because of the grilled chicken containing gluten), but it's still nice that they acknowledge those with gluten intolerance and have a coupon for us.
(I have no idea how well they do at preventing cross-contamination! That is something you will need to find out for yourself at the location you eat at and then decide whether or not you'll risk it.)
(I also have to say, I HATE their commercials! But they do make good burgers and they have Fanta in their soda machine.)