Arrowroot Powder
A flavorless white powder that turns sauces silky and clear, not cloudy, which is the one thing cornstarch can't quite manage.
What It Is
Arrowroot comes from the roots of a tropical plant native to South America and long cultivated across the Caribbean. The starch is dried and ground to a fine, chalky powder. It thickens at a lower temperature than cornstarch and leaves sauces, glazes, and fruit fillings glossy and transparent rather than dull and opaque.
It works well in delicate sauces where you want the color of the food to show through. It also holds up better in acidic dishes, like a lemon curd or a cherry glaze, where cornstarch can break down and turn thin.
What To Do
Mix arrowroot with a small amount of cold water before adding it to anything hot, about one teaspoon of powder per one teaspoon of cold water, stirring until smooth. Then stir that slurry into your sauce or filling over medium heat and watch it thicken quickly. Pull it off the heat as soon as it clears. Overcooking breaks the thickening power and you are back to thin.
Use about one teaspoon of arrowroot for every one tablespoon of cornstarch a recipe calls for. Store it in a cool, dry spot in a sealed container and it will keep for a year or more.
