1. Bring water to a simmer in a

large pot. Remove from heat, and

add vinegar and 2 tablespoons

salt, stirring until salt dissolves.

Add potatoes, and let sit 1 hour.

2. Preheat oven to 450°. Drain

potatoes, and pat dry. Toss potatoes

with 2 tablespoons oil,

2 teaspoons salt, and the cornstarch.

Divide remaining oil

between 2 rimmed baking sheets,

and place in oven until oil is almost

smoking, about 5 minutes.

3. Divide potatoes between

baking sheets, and roast until

golden brown and cooked

through, about 35 minutes, rotating

sheets and flipping potatoes

halfway through. Season with

salt, and serve warm or at room

temperature.