Toro Brand produces lots of gluten free baked good mixes. From bread to sponge cake, these items are vegan friendly. At least, the box contents are vegan friendly. I cannot speak for the baking instructions, as they will surely involve adding some liquids.
Sponge Cake Ingredients: Specially processed wheat starch, glucose, potato starch, salt, vegetable fat (palm oil), baking powder (calcium phosphate, sodium hydrogen carbonate), thickening agent (xanthan gum).
Note: the pancake / waffle mix is NOT vegan. It contains skim milk.
For more information, check out this Toro Box link.