Amaretti all'Alchermes

You may already be familiar with Alchermes, a scarlet-hued Italian liqueur that is called for in cakes and trifles and other desserts. It has an air of mystery about it, and no wonder. It is said to be derived from an 8th Century potion called confectio alchermes. Used, once upon a time, to calm heart palpitiations and fend off other maladies, confectio…