Grease and line a large baking sheet with nonstick baking paper.
Crush the cardamom pods using a pestle and mortar to release the seeds. Remove the shells and crush the seeds until fairly finely ground.
Whisk the egg whites in a thoroughly clean bowl until peaking. Sift the cornflour and chilli powder into the bowl and sprinkle in the crushed cardamom. Add the sugar and ground almonds and gently fold the ingredients together to make a sticky paste.
Place in a piping bag fitted with a 1 cm (½ inch) plain nozzle and pipe fingers, 5 cm (2 inches) long, onto the baking sheet, spacing them slightly apart.
Bake in a preheated oven, 180°C (350°F), Gas Mark 4, for 10–12 minutes until crisp and pale golden. Transfer to a wire rack to cool.