These were the best roast potatoes I’ve ever made. They were the crispiest I’ve ever done. The point of the recipe is to ‘rough up’ the surface of the potatoes. That enables them to crisp up as well as they do. I didn’t have any duck fat, so I used good bacon grease – rendered chicken fat would also work. I also halved the recipe and didn’t use the thyme (didn’t have any).
4 1/2 pounds russet potatoes rinsed, peeled if desired, and cut into 2-inch chunks
1 tablespoon white vinegar
Kosher salt
1/4 cup duck fat
Freshly ground black pepper
12 sprigs thyme
Recipe
Place the oven racks in the lower and upper positions and heat the oven to 500F. Put the potato pieces in a large pot and cover with cold water by 1-inch. Add 2 tablespoons of the salt and the vinegar. Over high heat, bring to a boil. Lower the heat to a simmer and cook until the outer layer is tender. The middle should still show some resistance to a knife. Drain and place in a large bowl.
Add the fat to the hot potatoes. Season with salt and pepper to taste and toss well with a large metal spoon. This should ‘rough up’ the potatoes and coat each piece with some of the fat.
Place the potatoes on two large baking sheets (I lined mine with non-stick foil) – giving each piece plenty of room. Drape the thyme sprigs over.
Place in the oven and roast for about 20 minutes – or until the bottoms of the potatoes are crisp and golden. Rotate the trays midway and move the top tray to the bottom and vice-versa. Flip the potatoes over and roast for another 20 minutes, or so. They are done when every potato is golden and crisp all the way around.