Cornstarch: Complete Baking Guide
Thickens, tenderizes, and creates crunch
What Cornstarch Does in Baking
Cornstarch is a pure starch extracted from corn. In baking, it's used to thicken fillings and custards, tenderize cakes by diluting the protein in flour, and create an ultra-crisp coating on fried or baked items. Adding 2 tbsp cornstarch per cup of all-purpose flour creates a close approximation of cake flour.
Key Properties
- ▸Twice the thickening power of all-purpose flour
- ▸Gluten-free thickener for pie fillings and pastry cream
- ▸2 tbsp cornstarch + 14 tbsp flour ≈ 1 cup cake flour
- ▸Creates glossy, clear gels when used in fillings
- ▸1 cup = 128g
Quick Measurement Reference
| Cups | Grams |
|---|---|
| ¼ cup | 32g |
| ½ cup | 64g |
| 1 cup | 128g |
| 2 cups | 256g |
Expert Baking Tips
- 1Always mix cornstarch into a cold liquid (slurry) before adding to hot mixtures — adding it dry causes lumps.
- 2For pie fillings, use 2–3 tbsp cornstarch per 4 cups fruit to get the right consistency.
- 3Add cornstarch to cookie dough for extra tender, bakery-style texture.
- 4Don't freeze cornstarch-thickened fillings — cornstarch breaks down and weeps on thawing.
⚠️ Common Mistakes to Avoid
- ✗Adding cornstarch directly to hot liquid — it clumps instantly. Always make a slurry first.
- ✗Overcooking a cornstarch-thickened sauce — it can thin out again if heated too long.
- ✗Freezing cornstarch-thickened pie fillings — the texture turns watery and grainy on thawing.