Cornstarch (or corn flour) is a fine, powdery flour made from the endosperm of corn kernels. We use cornstarch as a thickener for sauces, puddings and even stir-fries. To avoid lumps always mix cornstarch with liquid before adding it to the dish you wish to thicken.
If you don't have cornstarch you can substitute one of the following per tablespoon needed:
3 tablespoons all-purpose flour (must be cooked a few minutes to get rid of the raw flour taste)
OR> 1 to 1 1/2 tablespoons arrowroot (makes the sauce glossy)
OR> 1 to 1 1/2 tablespoons quick cooking tapioca OR> 2 teaspoons potato starch OR rice starch or instant mashed potato flakes.
See Keto substitutes for cornstarch below.
If you are on a Keto or other low carb eating plan then you may want a thickener that is lower in carbohydrates such as:
Chia seeds - per tablespoon of cornstarch called for use 1 teaspoon chia seeds at a time until the desired consistency is achieved.
Almond Flour - this high protein flour works well as a thickener.
Xanthan gum - A common food additive used as a thickener in salad dressings and other processed food products.