If you have a food processor or Ninja, you can make powdered sugar.

When processing this, the sugar will heat up quickly. Give it a few seconds between pulses or it could glue the processor lid to the bowl, and it's very hard to get unstuck again.

Don't use the functions on the processor or blender that runs the machine for several seconds or minutes! Pulse only, and give it some time to cool off between pulses.

Sugar that's been made into a powder will compact a bunch once powdered.

All commercially made powdered sugar has a certain amount of cornstarch mixed into it. Sometimes I use no cornstarch at all in my powdered sugar. And other times it's approximately a teaspoon of cornstarch to one cup granulated sugar. That goes into my Ninja mixing bowl, seal the lid on, set it up, and pulse a few times until it's the consistency needed, being sure to allow the Ninja to cool between pulses.

This way there's no chance of buying a box or bag of powdered sugar from the store that tastes like laundry soap or someone's perfume.. as has happened to me.