It’s not that I regularly make my own powdered sugar—or that buying some is particularly strenuous or expensive—but it’s handy to know how to for two big reasons.
Sometimes you find yourself without it and the thought of running to the grocery store doesn’t appeal in the slightest. Or you want the results of powdered sugar with something other than white sugar (I’ve made it with raw cane sugar and coconut sugar, but you can turn nearly any type of granulated sugar into powdered in minutes). This may be because you’d rather use natural sweeteners or to satisfy a dietary concern or that’s what you have to use up. Either way, the flavor won’t be affected.
Powdered sugar is just white sugar that has been finely ground into a powder. When it’s made commercially, it has starch added to prevent caking, but it also plays a role in recipes: Think about royal icing or a basic glaze. They start out fluid and soft, but set up shiny and firm (thanks, starch!). To make your own powdered sugar at home, that’s all you’ve got to do—grind up some granulated sugar and add a small amount of starch.
Here’s how to do it:
You can use any one of the following tools: a clean/dry coffee or spice grinder, a high powered blender, or a food processor. The coffee/spice grinder is the most efficient, but obviously can only handle a small quantity at a time, so a high powdered blender or a food processor is the next best thing.
Weigh out an amount of sugar, and add it to the blender or food processor (1/2 cup of granulated sugar will make about 1 cup powdered sugar, but that will vary slightly based on the type of sugar you use). Pulse on high speed until the sugar is no longer visibly granulated, but instead resembles a fine powder. This can take 2 to 5 minutes, depending on the amount of sugar and the machine you’re using.
Transfer your now-powdered sugar to a large sieve and add 3% of the sugar’s original weight in cornstarch. So if you started with 10 ounces of sugar, add 0.30 ounces of cornstarch, and sift the two together 2 to 3 times to combine. You can store the powdered sugar in an airtight container, or use immediately as you would the store-bought kind.
Then, get baking:
What's your favorite use for powdered sugar? Let us know in the comments!