Adapted from
DessertsForTwo.com Mini Lemon Cakes* Test the potency of your baking soda by mixing a little bit with some lime juice. You want it to start bubbling like crazy, otherwise you'll need new fresh baking soda.
** I left the butter out for too long, so it was quite soft, this will also help in giving you more of a glaze than a thick frosting.
***The cake itself is vegan but the frosting uses cream cheese and butter, but if you have dairy-free versions available I think you could make the cake 100% vegan.