How To Make Powdered Sugar Without Cornstarch | Smooth Icing, No Grit

Blend granulated sugar into a fine powder, sift it, then store it airtight; a pinch of arrowroot can help keep it free-flowing.

Sometimes you want powdered sugar with nothing extra mixed in. Maybe you can taste the starch in a glaze. Maybe you’re baking for someone who avoids corn. Or you ran out mid-recipe and you’re not driving to the store for one cup of dusting sugar.

Good news: cornstarch-free powdered sugar is simple. It’s just sugar ground smaller, plus smart handling so it stays soft, fluffy, and easy to measure. The trick isn’t “blend longer forever.” The trick is heat control, the right batch size, and sifting like you mean it.

This recipe gives you two versions: a pure two-ingredient method (sugar only), and an option with a tiny amount of a non-corn starch that helps reduce clumping. Pick the one that fits your pantry and your use.

Why Store-Bought Powdered Sugar Usually Has Cornstarch

Most grocery-store powdered sugar is finely milled sugar blended with a small amount of starch. That starch helps it pour, slows clumping in humid air, and keeps the powder from packing hard in the bag.

When you make your own, you’re skipping that anti-caking helper. That’s fine. It just means storage and timing matter more. Freshly ground sugar is at its fluffiest right after you sift it, so it’s a smart move to make what you’ll use within a week or two.

Tools That Work And Tools That Fight You

You can make a great batch with common kitchen gear. You don’t need a fancy setup, but you do need enough speed to grind sugar crystals down to dust.

Best Options

• High-speed blender: Fast, fine texture, larger batches.
• Coffee/spice grinder: Great for small batches and quick refills.
• Food processor: Works in a pinch, but often stays a touch coarser.

Must-Have Small Stuff

• Fine-mesh sieve (or flour sifter)
• Measuring cup and spoon
• Airtight jar with a tight lid

One Warning That Saves A Batch

Sugar can warm up fast when it’s spinning at high speed. Warm sugar can start to clump in the jar, even if it looked perfect coming out of the blender.

So you’ll use short blending bursts, and you’ll let the powder cool for a minute before sealing it up. That’s it. No drama.

Recipe Card

Cornstarch-Free Powdered Sugar

Yield: About 2 cups powdered sugar (from 2 cups granulated sugar)

Time: 5 minutes

Ingredients

• 2 cups granulated sugar
• Optional: 1 teaspoon arrowroot powder or tapioca starch (non-corn), for reduced clumping

Instructions

1. Add the granulated sugar to a dry blender jar or grinder.
2. Blend on high in short bursts, stopping to shake the jar once or twice, until it looks like soft dust.
3. Pour the powder through a fine-mesh sieve into a bowl. Push gently with a spoon to help it pass through.
4. Return any coarse bits in the sieve to the blender and blend again for 10–15 seconds, then sift again.
5. If using arrowroot or tapioca, whisk it in after the final sift.
6. Let the powdered sugar sit uncovered for 2 minutes to cool, then seal in an airtight jar.

Storage

• Room temp, airtight: 2–4 weeks
• For best texture: use within 1–2 weeks, especially in humid kitchens

Notes

• Start with dry tools. Any moisture turns sugar into paste fast.
• If your blender runs hot, make smaller batches (1 cup at a time).

How Fine Should It Be

If you’re dusting brownies or French toast, you can get away with slightly coarser powder. If you’re making icing for cookies, you want it as fine as you can make it, plus a sift. That sift step is the difference between “silky” and “tiny crunchy bits.”

If you’re curious about nutrition, powdered sugar is still sugar. The texture changes, not the basic nutrient profile. USDA FoodData Central is a solid place to sanity-check numbers for powdered sugar and serving sizes. USDA FoodData Central

One more texture detail: homemade cornstarch-free powder can melt faster into liquid than many bagged brands. That’s great for glazes and quick icings. It can make a frosting feel a touch softer too, so you may use a spoonful less liquid than you usually do.

Method	What You’ll Get	Best Uses
High-Speed Blender (2-cup batch)	Fluffy, fine powder after sifting	Glazes, icing, dusting, frostings
Coffee/Spice Grinder (1/2–1 cup batch)	Very fine powder, fast	Small-batch icing, quick refills
Food Processor (2-cup batch)	Often slightly gritty unless sifted twice	Dusting, simple glaze
Single Sift	Good texture, small grit risk	Pancakes, waffles, dusting fruit
Double Sift	Cleaner, smoother powder	Royal icing, cookie icing
Sugar Only (No Added Starch)	Pure sugar taste, can clump sooner	Glazes, drinks, fresh use
Optional Arrowroot Or Tapioca (1 tsp per 2 cups sugar)	Less clumping, still cornstarch-free	Storage past 2 weeks, humid kitchens
Make-Ahead And Cool 2 Minutes	Less moisture trapped in the jar	Any method, better shelf texture

How To Make Powdered Sugar Without Cornstarch For Frosting

Frosting is where texture gets picky. You’re not just sprinkling. You’re building a creamy structure where every grain shows up.

Do This For Smooth Frosting

• Blend in smaller batches: One cup of sugar grinds more evenly than a packed blender jar.
• Sift twice: First sift removes the big bits. Second sift catches the “almost fine” bits that still feel gritty in frosting.
• Measure after sifting: Powdered sugar fluffs up. Measuring before sifting can throw off your ratio.

Buttercream Tip That Saves The Texture

Start with room-temp butter that dents when pressed, then beat it until it looks lighter. Add the powdered sugar in stages. If you dump it all at once, it packs into the fat and can form little dry pockets that take longer to smooth out.

If your frosting turns runny, don’t chase it with more liquid. Add more cornstarch-free powdered sugar a spoon at a time, mix, then pause and check. Homemade powdered sugar dissolves fast, so the frosting can loosen as it sits for a minute.

How To Use It In Glazes, Icing, And Dusting

This homemade version shines in glazes. Since it melts quickly, you can get a smooth drizzle with less stirring.

Easy Glaze Ratio

• 1 cup cornstarch-free powdered sugar
• 1–2 tablespoons milk, water, citrus juice, or coffee
• Pinch of salt (optional)

Stir, rest 30 seconds, then stir again. That short rest lets tiny dry pockets absorb liquid, so you don’t over-thin the glaze.

Dusting Without A Sugar Cloud

For a neat finish on brownies or pancakes, sift the sugar through a small sieve over the food. Hold the sieve close to the surface. Short shakes beat big swings.

Common Problems And Fast Fixes

If you’ve tried this once and didn’t love the result, it’s usually one of three issues: the grind wasn’t fine enough, the sugar warmed up, or moisture got into the jar. All three are easy fixes.

Problem	What’s Going On	Fix
Gritty icing	Powder still has larger crystals	Blend 10–15 seconds more, then sift again (twice for icing)
Clumps in the jar	Warm sugar sealed too soon, or humid air	Cool 2 minutes before sealing; store airtight; add 1 tsp arrowroot or tapioca per 2 cups
Powder turns into a paste	Moisture from tools, steam, or wet spoon	Use dry tools only; keep jar away from the stove; replace lid fast
Blender “sugar smoke” cloud	Powdered sugar dust lifts when opened fast	Wait 30 seconds before opening; crack lid slowly
Not as white as store-bought	Some brands add starch that lightens and dries the mix	Sift twice; use white granulated sugar; avoid raw sugar for this
Frosting tastes too sweet	Homemade powder dissolves fast, so sweetness hits sooner	Add a pinch of salt and a splash of acid (lemon) to balance
Hard block after a week	Humidity + no anti-caking help	Break it up, re-blend, re-sift; store with a tight lid in a cool cupboard

Flavor Notes And Ingredient Swaps That Still Fit The Goal

If you want pure sugar only, stick to granulated white sugar. If you’re fine with “no corn” but you still want a less-clumpy jar, arrowroot and tapioca are common pantry picks.

If corn avoidance is allergy-related, read labels on any optional add-ins. Different brands handle cross-contact in different ways. If you’re checking what cornstarch is listed as in regulatory ingredient references, FDA’s food substance listing is one place it appears. FDA food substance listing for cornstarch

One swap to skip: brown sugar. Grinding it makes a damp, sandy powder that clumps fast and can turn sticky in storage. It can be fun for a quick dusting on baked apples, but it won’t behave like classic powdered sugar.

Best Storage Habits For Cornstarch-Free Powder

Your storage plan decides whether this stays fluffy for weeks or turns into a brick. You don’t need special containers, just tight ones.

Do This

• Use a glass jar with a solid lid, or a plastic container with a gasket seal.
• Keep it in a cool cupboard, away from the stove and dishwasher steam.
• Scoop with a dry spoon every time.

If It Clumps Anyway

Don’t toss it. Break it up with a fork, re-blend for 10 seconds, then sift. It comes right back.

Batch Sizes That Match Real Kitchens

For most home baking, a 2-cup batch is the sweet spot. It’s enough for a frosting or a couple of glazes, but not so much that it sits for months and grabs moisture.

If you only need a dusting, make 1 cup. A small batch is faster to grind fine, cools quicker, and stores better in a small jar.

Quick Checklist Before You Start

• Dry tools and dry jar
• Blend in short bursts
• Sift once for dusting, twice for icing
• Cool 2 minutes before sealing
• Store airtight, away from steam

Once you do it a couple of times, it feels like making your own breadcrumbs. Simple, fast, and one less store run.