Yes, you can substitute for Xanthan Gum in gluten-free baking. Since the Xanthan Gum is used as a binder in place of the gluten protein, you'll need to use a different baking binder so you finished product will have the appropriate texture and won't crumble. The best subs for Xanthan Gum are Guar Gum or a Gum-free Baking Binder made from psyllium husk powder and potato starch.