Ultra Crispy Potatoes with Parmesan

3 pounds russet potatoes, peeled and cut into 1 1/2- to 2-inch chunks
1/2 teaspoon baking soda
2 tablespoons kosher salt, or 1 tablespoon table salt
4 dried bay leaves, preferably Turkish
1 tablespoon whole black peppercorns
6 whole garlic cloves, peeled and lightly crushed
3 to 4 thyme or rosemary sprigs, or a mix
3 tablespoons unsalted butter, melted
2 ounces finely grated Parmesan (about 1 cup)
Kosher salt and freshly ground black pepper

Adjust oven rack to center position and heat to 425 degrees, or 400 degrees if using convection. (Convection is recommended, if available.) Combine potato chunks, 2 quarts water, baking soda and salt in a large saucepan.

Cut a 10-by-10-inch square out of cheesecloth and place bay leaves, peppercorns, garlic cloves and herb sprigs in the center. Gather up the corners of the cloth into a pouch, and tie off with butcher’s twine. Add bundle to the pot with potatoes, and set over high heat. Bring to a boil, and cook until you can poke a knife into a larger chunk of potato without any resistance, about 10 minutes after the water comes to a boil.

Drain potatoes in a colander and discard aromatic bundle. Line a 13-by-18-inch rimmed aluminum baking sheet with parchment paper.

Transfer potatoes to a large bowl. Add melted butter and Parmesan. Season lightly with salt and pepper. Toss and fold with a rubber spatula until Parmesan, butter and starch form a slurry over the surface of the potatoes, about 30 seconds. Transfer potatoes to the prepared baking sheet and spread out so they are mostly separated from one another. (At this point, they can be allowed to cool, then transferred to a sealed container and stored in the refrigerator until ready to roast.)

Transfer baking sheet to oven and roast potatoes until pale golden brown and sizzling on the bottom, about 20 minutes. Flip potatoes using a thin metal spatula and continue roasting until crisp and blond-gold on most sides, about 15 to 20 minutes longer. (Check frequently toward the end, and don’t allow the potatoes to cook beyond a deep gold, or they will turn bitter.)

Remove potatoes from oven and allow to cool for 5 minutes on the pan before transferring to a serving platter.

Super Crispy Potatoes

Kosher salt
1/2 teaspoon (4g) baking soda
4 pounds (about 2kg) russet or Yukon Gold potatoes, peeled and cut into quarters, sixths, or eighths, depending on size (see note)
5 tablespoons (75ml) extra-virgin olive oil, duck fat, goose fat, or beef fat
Small handful picked rosemary leaves, finely chopped
3 medium cloves garlic, minced
Freshly ground black pepper
Small handful fresh parsley leaves, minced

Adjust oven rack to center position and preheat oven to 450°F/230°C (or 400°F/200°C if using convection). Heat 2 quarts (2L) water in a large pot over high heat until boiling. Add 2 tablespoons kosher salt (about 1 ounce; 25g), baking soda, and potatoes and stir. Return to a boil, reduce to a simmer, and cook until a knife meets little resistance when inserted into a potato chunk, about 10 minutes after returning to a boil.

Meanwhile, combine olive oil, duck fat, or beef fat with rosemary, garlic, and a few grinds of black pepper in a small saucepan and heat over medium heat. Cook, stirring and shaking pan constantly, until garlic just begins to turn golden, about 3 minutes. Immediately strain oil through a fine-mesh strainer set in a large bowl. Set garlic/rosemary mixture aside and reserve separately.

When potatoes are cooked, drain carefully and let them rest in the pot for about 30 seconds to allow excess moisture to evaporate. Transfer to bowl with infused oil, season to taste with a little more salt and pepper, and toss to coat, shaking bowl roughly, until a thick layer of mashed potato–like paste has built up on the potato chunks.

Transfer potatoes to a large rimmed baking sheet and separate them, spreading them out evenly. Transfer to oven and roast, without moving, for 20 minutes. Using a thin, flexible metal spatula to release any stuck potatoes, shake pan and turn potatoes. Continue roasting until potatoes are deep brown and crisp all over, turning and shaking them a few times during cooking, 30 to 40 minutes longer.

Transfer potatoes to a large bowl and add garlic/rosemary mixture and minced parsley. Toss to coat and season with more salt and pepper to taste. Serve immediately.

Extra Crispy Potatoes

4 1/2 pounds (2kg) russet potatoes (see note), rinsed, peeled if desired, and cut into 2-inch chunks
Kosher salt
1 tablespoon (15ml) white vinegar
1/4 cup (60ml) duck fat (see note)
Freshly ground black pepper
12 sprigs thyme

Adjust oven racks to lower and upper positions and preheat oven to 500°F (260°C). Place potatoes in a large saucepot and cover with cold water by 1 inch. Add 2 tablespoons (28g) salt and vinegar. Bring to a boil over high heat, reduce to a simmer, and cook until exteriors are tender, about 5 minutes. Potatoes should show slight resistance when poked with a paring knife or a cake tester. Drain potatoes and transfer to a large bowl.

Add fat to bowl with potatoes. Season with pepper and more salt to taste, then toss with a large metal spoon until exteriors are slightly bashed up and coated in a thin layer of potato/fat paste. Divide potatoes evenly between 2 heavy rimmed baking sheets. Spread thyme sprigs over potatoes.

Transfer baking sheets to oven and roast until bottoms of potatoes are crisp and golden brown, about 20 minutes total, swapping trays top for bottom and rotating them once halfway through roasting. Using a thin metal spatula, flip potatoes and roast until second side is golden brown, another 15 to 20 minutes. Discard thyme sprigs and serve.