I been making french macaroons at home and i am on my third attempt. I notice some people use caster sugar and some recipes say regular sugar. which is better and does it make a difference? If so, how? thanks!
Commercially produced caster sugar uses a process that results in crystals that are uniform in size. The trouble with grinding it yourself will be the unevenness of the grind. The crystal size may range from powder to slightly smaller than normal size crystals.
Using the Italian method, the size/type of crystal does not matter... have you considered that method? Which process are you using to make the meringue?