So, why the weird ratio? Well, it's because powdered sugar is, quite literally, powdered – it's been ground into a fine powder, which makes it much sweeter than granulated sugar. This is because the particles are smaller, so they dissolve faster and release more sugar goodness into your baked goods. It's like a sugar bomb just waiting to happen!
Powdered sugar also contains a small amount of cornstarch, which helps prevent it from becoming lumpy. This is great for preventing clumps in your frosting or glaze, but not so great when you're trying to substitute it for granulated sugar in a recipe. That's why you need to use a bit more of it – to account for the extra ingredients.
The difference between unrefined, raw, and refined sugars
Now, I know what you're thinking: "But what about the flavor?" Will using powdered sugar instead of granulated sugar affect the taste of my baked goods? The answer is, thankfully, no. The flavor will remain the same, because powdered sugar is still, well, sugar. It's just been processed a bit differently, that's all.
