Tips & Techniques > Making Roux with Potato Starch
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Potato starch can be substituted for flour when making roux:
1 tablespoon of potato starch + 1 tablespoon of butter/fat will thicken 1 cup of liquid.
Potato starch can lose its thickening power if brought to a boil for too long. Make sure to monitor the heat and simmer the soup or sauce. Potato starch is an ideal substitution for people who are gluten intolerant.