How to Replace Powdered Sugar
If you need a dusting finish (like on top of a cake or brownies) and you have none of the above, reach for cocoa powder. Unsweetened cocoa looks fancy and tastes amazing. Just make sure it’s not a chocolate-dusted disaster if your dish isn’t chocolate-friendly.
How To Substitute Equal For Sugar In Recipe at Clayton Cooper blog
You can also use finely ground almond flour or coconut flour. It won’t be sweet, but it’ll give you that pretty, snow-like look. It’s the baking equivalent of putting a hat on a messy hair day—it covers up the chaos.
And hey, if you’re truly out of options, just tell your guests you’re going for a "rustic, European" look. Nobody can argue with that. They’ll nod, smile, and secretly think you’re a genius.