Macaron (French macaroon)

Method
Prep:30min  ›  Cook:10min  ›  Ready in:40min 

1. Line a baking tray with a silicone non-stick baking mat.
2. Beat egg whites in the bowl of a stand mixer fitted with a whisk attachment until whites are foamy; beat in caster sugar and continue beating until egg whites are glossy, fluffy, and hold soft peaks. Sift icing sugar and ground almonds in a separate bowl and quickly fold the almond mixture into the egg whites, about 30 strokes.
3. Spoon a small amount of batter into a plastic bag with a small corner cut off and pipe a test disk of mixture, about 4cm in diameter, onto prepared baking tray. If the disk holds a peak instead of flattening immediately, gently fold the mixture a few more times and retest.
4. When batter is mixed enough to flatten immediately into an even disk, spoon into a pastry bag fitted with a plain round tip. Pipe the mixture onto the baking tray in rounds, leaving space between the disks. Let the piped macarons stand out at room temperature until they form a hard skin on top, about 1 hour.
5. Preheat oven to 140 degrees C.
6. Bake macarons until set but not browned, about 10 minutes; let cool completely before filling.