Preheat oven to 350°F. Crumble foil, then unfold it and use it to line cookie sheets. Do not line with paper. The crumbled foil will help the cookies not stick. Whisk together flour, cocoa and sugar. Beat egg whites and salt until soft peaks form. Add almond extract. Sift sugar mixture on top 1/2-cup at a time, beating slowly then fast until all the sugar is incorporated. Scrape down sides with every batch. Fold in the nut meal. For cutout cookies:Sprinkle confectioners' sugar on parchment paper and place dough on top, sift/sprinkle with more sugar. Place another paper on top and roll out to 1/4" thick. Lift paper, sprinkle more sugar, place it back on and flip everything. Remove top liner. Cut Shapes and gently place on a your prepared cookie sheet. For round cookies: roll 1" balls and flatten between palms then drop on prepared sheet (do not press them onto sheet). Bake 12 min. Transfer entire liner to rack to cool completely. Carefully detach each cookie.