Need some cooking advice for someone hoping to cook for a girl with celiac disease.

There's a girl at work that I'd like to impress, possibly by baking a nice gluten-free cake of some sort to share with my colleagues on our weekly "cake day". I don't want to impose on her though because I realise she usually has to be very careful about what she eats and prefers to cook for herself, but I feel kind of sorry for her when she gets left out.

Can I do this as a surprise or should I be double-checking my recipe first with her?

Also I'll need a good recipe :)