Preheat oven to 160C (320F). Line a large tray with baking or parchment paper.

Whizz pecans in a food processor until finely ground. Combine ground pecans, sugar, cocoa powder and egg whites in a bowl.

Spoon into 1 tablespoon piles on the baking tray. Allow room for them to spread.

Top each with pecan halves.

Bake for 12-15 minutes or until puffy and starting to crack. Cool on the tray.