Double-fried french fries

Peel the potatoes, square them off and slice into quarter-inch sheets, then quarter-inch fries.

Put the potatoes in a large pot of water with two to three large pinches of salt and 1 tbsp vinegar per quart of water.

Bring to a boil, stirring occasionally, and boil about 5 minutes until tender but with a slight bite.

Lift onto a paper-towel-lined baking sheet to dry. Drain and dry the pot, add about two inches of frying oil and heat on high to 400F, checking with a thermometer.

In three small batches, fry the fries for 50 seconds each, then dry on a second lined sheet.

Cool to room temperature about 30 minutes, or freeze for on-demand fries.

Return the oil to 400F, fry the frozen fries in batches until they just float and are lightly golden brown, about 3 minutes; toss in a strainer with salt.