Ossi dei morti almond biscuits

I coarsely chop almonds with a knife.I mix flour, sugar, vanilla and baker's ammonia in a bowl. Use little ammonia, a scant half teaspoon, and do not smell it as very strong.I mix and add egg whites.I stir in chopped almonds.The mixture is sticky. I flour work surface, turn out dough, flour the top and flatten.I form a long flattened log about 1 cm thick. I cut biscuits with a knife.I flour well and rest at least 2 or 3 hours.I turn biscuits upside down onto a parchment-lined tray, spaced apart.I bake at 170°C for 25 minutes, reduce to 100°C and leave another 10 minutes to dry thoroughly and become crisp. They harden more on cooling. Store cold in a tin.