MethodWhisk custard, yoghurt, chilli, NESQUIK and icing sugar in a bowl until combined.
Combine gelatine and 3 tablespoons water in a small saucepan and stir over low heat until gelatine dissolves and liquid is clear. Remove from heat and allow to cool slightly.
Beat eggwhites in a clean, dry bowl until soft peaks form.
Fold eggwhites and gelatine mixture through chocolate mixture. Divide between 6 serving glasses and refrigerate until set.
Serve topped with berries, if desired, and chocolate.