Huh, I never really thought about it in the context of "what if you turned toast to powder?"

Powdered toast, also sometimes called cinnamon toast, is where you toast some bread and add some butter while it's toasting so that it's toasty and buttery. Then, you sprinkle on some "cinnamon-sugar," aka, powdered cinnamon and granulated sugar mixed together, which sticks to the melted butter.