The Best Deep-Fried French Fries

Double-fried, ultra-crispy homemade fries with a fluffy interior, made from carefully chosen starchy, low-moisture potatoes.

Ingredients

—		starchy, low-moisture potatoes (e.g. russets)
—		vegetable oil, for deep-frying
1 cup	240 ml	salt, for the saline moisture test
1 tbsp	15 ml	vinegar (per 3.7 L water)
to taste		salt, for finishing

Pick the right potatoes. The best frying potatoes are high in starch and low in moisture. To test each one, dissolve 1 cup of salt in 8–10 cups of water, drop the potatoes in, and observe: floaters are high-moisture (set them aside for another dish), while those that sink or hang in the middle are low-moisture and perfect for frying.
Cut and soak. Cut the potatoes into fries. Soak them in a bowl of ice water with 1 tablespoon of vinegar per 3.7 L of water (the vinegar keeps them from oxidising and discolouring, and the soak pulls out starch for a soft inside and crisp outside). Refrigerate at least 2 hours and up to 12 hours.
First fry. Drain and pat the fries completely dry. Preheat the deep fryer to 149–162°C (300–325°F). Fry for about 5–7 minutes — they should stay pale but turn soft. Lift out, drain on paper towels and let cool.
Second fry. Increase the oil to 182–190°C (360–375°F). Fry the potatoes in batches so they have room to swim and brown faster, about 2–4 minutes, until as golden as you like.
Lift the basket and drain the fries on a fresh layer of paper towels, then salt them immediately while hot. Serve at once.