What's the secret to making fries that can be reheated?

I hear this one a lot here in Canada, usually after a batch goes soggy in the fridge overnight.

Catering fries survive reheating because they are coated foodservice fries. The home version of the same trick is the double fry.

Parboil the cut potatoes first and rough up the edges. Fry them once, then freeze them solid on a tray.

Fry them again straight from frozen. That second fry is what brings the crisp back on the reheat, instead of a limp, soggy fry.

Asked on r/Cooking

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