<<Disclaimer: Verify this information before applying it to your situation.>>

You know how we have trouble with crumbly gf cakes?   If you make them
in mini-cup cake or madeline pans, they come out perfect.  Follow your
usual recipe and reduce baking time to roughly 12 min [give or take a
min or two]

Classic madelines are a sponge cake recipe, often made with cake flour
{for which cornstarch can be subsituted, cup for cup}, so it is not a
stretch
Ann