"This is definitely our favorite potato recipe, and one of our favorite dishes in general!" Angie Rito and Scott Tacinello, the husband-and-wife team behind Don Angie, told Insider. "We love that the tangy creamy Italian dressing and sumac spice mix both offer acidity to balance the sweetness of the potatoes. The Parmesan and chives add even more savoriness, resulting in a very craveable dish."
To make the Japanese sweet potatoes for six, you'll need: 4 medium Japanese sweet potatoes (scrubbed clean), 2 heads of garlic (sliced in half horizontally), and Kosher salt.
First, place your potatoes and garlic in a large pot and cover with cool water by an inch. Heavily season it with salt ("like seawater") and bring it to a simmer over medium heat. Cook the potatoes for 25 to 30 minutes, until they're fork-tender. Drain the potatoes and set them aside until they're cool enough to handle but still warm.
Then, with a fork, gently break the potato apart into rustic pieces about 1 ½ to 2-inches in size. Add the pieces to a large mixing bowl and toss with 1 cup of potato starch, evenly coating all slides.
"It's important that the potatoes are still warm at this point. The residual heat helps the starch adhere and activates it," Rito and Tacinello told Insider. "This step ensures a very crisp outer coating when you fry the potatoes."
Arrange the potatoes in a single layer on a sheet tray or large plate and place them in the refrigerator to chill for 45-60 minutes.
While your potatoes are cooling, make the spice mixture: Add 2 tablespoons granulated onion, 2 tablespoons granulated garlic, 2 tablespoons kosher salt, 2 tablespoons sugar, 1 tablespoon sumac, and ½ teaspoon dried oregano into a small bowl and whisk everything together until they're evenly combined. Set aside.
You can also make the dressing. Throw ⅓ cup creme fraîche, ¾ cup Kewpie mayonnaise, ¼ cup white wine vinegar, ⅓ cup coarsely grated Parmesan (preferably Parmigiano-Reggiano), 1 tablespoon garlic powder, 1 tablespoon onion powder, 1 ½ teaspoons dried oregano, 2 teaspoons sugar, 1 teaspoon kosher salt, ½ teaspoon black pepper, and ¼ cup of water all into a blender. Mix on high for 30 seconds, until they're well-combined.
Then, with the blender running on slow, slowly drizzle in ⅓ cup extra-virgin olive oil and ½ cup neutral oil (such as vegetable) for about 20 seconds, until they're well-incorporated. Set aside.
To fry your potatoes, first heat 8 cups of neutral oil in a large heavy-bottomed pot or Dutch oven over medium-high heat until it reaches about 360 degrees Fahrenheit. Then, working in batches to avoid overcrowding, fry your potatoes for 3-4 minutes, until they're golden brown and crispy. Set them in a large mixing bowl and toss with half of the spice mixture. Repeat the process until all your potatoes are fried and spiced.
Arrange your seasoned potatoes on a serving platter and drizzle with one cup of the dressing, putting the rest in a small side bowl for dipping. Garnish your potatoes with additional Parmesan and chives.
Pro tip: If you want to skip the hassle of frying, Rito and Tacinello said you can achieve a similar (but less crispy) result by cubing your potatoes, tossing them in olive oil, and roasting them in the oven for about an hour at 350 degrees Fahrenheit.