Why do you use caster sugar for anzac biscuits?

Caster sugar is used in ANZAC biscuits because it dissolves more easily than granulated sugar, resulting in a smoother texture and a more uniform mixture. Its fine granules help create a tender biscuit, contributing to the desired chewy consistency. Additionally, caster sugar can enhance the overall sweetness without making the biscuits grainy. Overall, it ensures a better balance of flavors and textures in the final product.