Roll out the pastry. Using a cutter, cut out approx. 28 circles (each approx. 5 cm in diameter). Place on a baking tray lined with baking paper.
Beat the egg white with the salt until stiff. Add the sugar and continue beating until the egg white turns glossy. Carefully fold the almonds and vanilla into the egg white using a rubber spatula. Transfer the mixture to a piping bag with a round nozzle (approx. 8 mm in diameter) and pipe nests onto the pastry bases.
Stir the jam, transfer to a disposable piping bag, cut approx. 1 cm off the tip, pipe the jam into the nests.
Approx. 15 mins. in the lower half of an oven preheated to 180°C. Remove from the oven, transfer to a cooling rack with the baking paper and leave to cool.
Dust the nests with icing sugar.