>> source: https://www.mashed.com/182903/how-to-make-powdered-sugar-from-granulated-sugar/
>> serves: 1 cup

In order to make your own confectioners' sugar, you will need a fairly #high-powered blender or a spice grinder{}. You should also add one tablespoon of @cornstarch{1%Tbsp} to each cup of @granulated sugar{1%cup}. Blend both ingredients on high for ~{30%seconds}, and guess what? You now have powdered sugar.

Note: Do not try this in a food processor, since this appliance will not be able to grind the sugar finely enough to turn it into a powder.