Alex Paffenroth, Paffenroth Gardens   (Photo: Marcus Nilsson)

Potato-and-Brussels-Sprout Gratin

THE CHEF:
Alex Guarnaschelli (Butter)
“This is the perfect seasonal side for Thanksgiving,” says Alex Guarnaschelli, who layers the dish with toasty bread crumbs, russet or huckleberry potatoes, and nutty sprouts, then binds it all together with cream to make it tender inside and crunchy on top.

THE FARMER:
Alex Paffenroth (Paffenroth Gardens) Warwick; 845-258-2539
Alex Paffenroth, a fourth-generation Hudson Valley farmer, credits the Union Square Greenmarket with saving his career. “I was originally an onion farmer but almost went out of business because of bad weather,” he says. To diversify, Paffenroth started selling basics, like leeks and squash, at the Greenmarket in 1990, then began following the requests for more exotic vegetables from the various chefs who became his regular customers. He has since expanded his farm to over 200 different vegetables, including 21 types of specialty potatoes, all of which flourish in the Hudson Valley region’s black-dirt soil.

THE RECIPE:
1 tablespoon unsalted butter
2 cloves garlic, minced
4 medium-size russet potatoes (about 3 pounds), peeled, and cut into thin slices
Kosher salt and white pepper
2 cups heavy cream
2 cups whole milk
Pinch ground nutmeg
1 cup grated Parmesan cheese
3/4 cup grated Gruyère cheese
2 tablespoons olive oil
11/2 pounds Brussels sprouts, trimmed and thinly sliced
2 teaspoons granulated sugar
Pinch paprika
1/2 cup bread crumbs
1/4 cup ground, toasted almonds

Preheat the oven to 350 degrees.

Grease a 12-inch gratin dish with butter. Sprinkle the minced garlic over the bottom of the dish.

Place potato slices in a saucepan and season with salt and pepper. Cover with cream, milk, and nutmeg; mix well. Place saucepan over low heat and simmer for 10 minutes. Do not stir the mixture too frequently, to avoid breaking the potatoes. Stir in ½ cup of Parmesan cheese and ½ cup of Gruyère cheese. Season with salt and pepper.

Heat the oil in a skillet; when it begins to smoke lightly, add Brussels-sprout slices and season with salt, pepper, and sugar. Sauté for 1–2 minutes, until they start to wilt slightly. Drain excess oil, sprinkle with paprika, and set aside.

Arrange of the potato-cream mixture in the bottom of the gratin dish. Top with of the Brussels sprouts and sprinkle with Parmesan and Gruyère cheese. Repeat the process twice more; pour remaining cream over the gratin and sprinkle with cheese.

Bake gratin until tender when pierced with a knife, 40 to 45 minutes. Combine the bread crumbs and almonds, sprinkle over the gratin, and bake for 10 minutes. Set aside to cool for about 20 minutes before serving.