Gluten free, nut free cake?

[bumpypaws]

MIL is 70 next week, and I need advice about her birthday cake!
She has coeliac disease, so absolutely no gluten! DH has a nut allergy, so absolutely no nuts!! FIL 'doesn't like fresh cream' (as well as anything else with any taste whatsoever - anyway...that's another thread!)
So..I'm looking for inspiration for a gluten free, nut free 'celebration' style cake! Can I just use y normal fail-safe sponge recipe but substitute gluten free flour? Or will I need to add anything else?
TIA

How about some sort of pavlova? would your FIL eat greek yog instead of cream maybe? (TBH I doubt you can please everyone and sounds like he's just faddy)

Lemon polenta cake > www.annabelkarmel.com/recipes/gluten-free/gluten-free-cake

I do make "normal" sponge cakes just swopping the flour tastes OK ....

My aunt has coeliac disease and I made the top tier of my sisters wedding cake gluten free using Doves Farm gluten free flour and using the recipe on the side of the packet. It came out well. I have also made this which was delicious, if you can get over the mental block of using potato.

I did Dan Lepard's gluten free lemon banana cake for a birthday party. It's quite small so I made two and stack them. They are nice.

Thanks all for the suggestions - will be doing some experimenting today, and I'll let you know how it goes.
GrimmaTheNome oh yes, faddy indeed!

Another vote for Doves gluten free flour....it makes all cakes yummy ;)

So, I made my normal sponge recipe with dove's gluten free self-raising flour, and added a tablespoon of milk for every 30g of flour, and it worked a treat! Didn't rise quite as well as my normal flour, but overall pretty good, so I'll be sticking with this, making a strawberry and buttercream 4 layer cake.
Thanks for the advice!