2nd, 3rd, and 4th attempts . . .little by little

As you may remember, I'm trying to develop a Ghana-style gluten-free shortbread cookie recipe.

I first tried using a couple of recipes from gluten-free friends/sites, but substituting coconut oil for the butter, and various blends of rice/millet/tapioca flours, etc. first for the main replacement of wheat flour and adding proportions of various gluten-free flours as indicated. Won't go into the specifics here, just say that the sugar didn't blend the way it does with butter, and the "tapioca flour," being tapioca starch, turned the dough either into a solid brick that I had to throw away and couldn't even roll out, or the cookies/biscuits were so gritty and crumbly they were not worth keeping.  I tried once with xantham gum and that still didn't work. Also, I was mixing the dough with a wooden spoon.

Yesterday, I tried substituting half powdered sugar for the sugar, and used a mixer, plus just cassava flour from Brazil (not the tapioca starch), and chilled the dough before rolling it out on parchment paper. This was the best yet, but according to Kwadwo, my reliable tester (and to myself, too), they still tasted gritty, and dry, and still were very fragile.

I'm going to keep experimenting and will keep you in the loop, but I'm wide open to suggestions: just remember I don't want to use things that aren't easily and cheaply available in Ghana. I'd like shortbread, because it uses only flour, sugar, butter substitute (like coconut oil--please no margarine), a little salt, and possibly a little flavoring like vanilla. If I can perfect this, I'll next try a gluten-free sugar cookie.