Make the amaretti biscuits a few hours in advance. Preheat the oven to 170°C. Beat the egg whites in a large bowl until firm. Gently fold in the liquor, sugar and the almonds into the egg white mixture.
Using a teaspoon, place dabs of the biscuit mixture onto a grease-proofed/lightly buttered oven tray. Leave space around each biscuit as the mixture will expand whilst baking.
Bake for 15 minutes. Transfer the biscuits on to a wire rack and allow to cool and harden up on the outside.
For the roast peaches and the caramel sauce, cut the peaches into small pieces and bake in the oven at 190°C with the balsamic vinegar, brown sugar and the butter for 10 minutes. Carefully remove the peach pieces from the baking dish, leaving the dark syrup. Add the cream to the syrup and stir gently over a low heat to create a deliciously sweet caramel sauce.
To serve place some warm peach pieces in to the bottom of a sundae glass (or large dessert bowl). Break up and sprinkle two amaretti biscuits on to the peaches. Add a scoop of ice-cream and a spoonful of whipped cream. Sprinkle chocolate pieces and the flaked almonds on top. Drizzle some of the caramel sauce all over the sundae and eat fast before someone else gets their paws on it!