I have begun Operation Christmas Cookie in earnest -- I made bourbon balls last night (haven't had them since I was a child and then I stumbled on the recipe in Dede Wilson's Baker's Field Guide to Christmas Cookies, and they are delicious. Wilson assures that they improve with age.) Anyway, another cookie I want to make is shortbread, and I'm thinking of using the recipe from the Three Chimneys Cookbook I bought in Scotland this summer. I've seen references on this board to shortbread improving with age, but I haven't seen that corroborated in any of the (many) cookbooks I've looked at. Can someone elaborate? Also, I'm considering using Land O Lakes Extra Creamy Butter. Will this affect the keeping quality? The Three Chimneys Recipe uses Rice flour.