POTATOES AU GRATIN WITH GRUYERE RECIPES

Steps:

• Heat the oven to 400ºF. Arrange a rack in the middle of the oven and heat the oven to 400ºF. Coat a 9x13-inch baking dish with 1 teaspoon of the unsalted butter.
• Grate the cheese. Grate 8 ounces Gruyère or sharp cheddar cheese on the large hole of a box grater and set aside.
• Thinly slice the potatoes and onions, and mince the garlic. Use a mandoline or a sharp chef’s to thinly slice 3 pounds Yukon gold or red potatoes into thin slices (no need to peel), doing your best to keep the potatoes slices stacked, as this will make assembly faster. Halve and thinly slice 1 small yellow onion. Finely chop 2 garlic cloves.
• Make the cheese sauce. Place the remaining 4 tablespoons butter and the garlic in a large saucepan over medium heat. Once the butter is melted, add 1/4 cup all-purpose flour, 1 teaspoon kosher salt, 1 teaspoon Dijon mustard, and 1/2 teaspoon black pepper. Whisk to combine and cook until fragrant, about 1 minute. Add 2 cups whole milk and whisk vigorously until well-combined. Bring the mixture to a simmer, whisking occasionally. Remove from the heat, add the cheese, and whisk until mostly melted and smooth.
• Layer the au gratin ingredients in the baking dish. Sprinkle the baking dish with about 2/3 of the sliced onions, arranging them in a single layer. Pour about 1 cup of the cheese sauce over the onions. Arrange the potatoes over the onions and cheese sauce — if you’ve kept them stacked, it is easy to fan them out into rows with the potatoes at an angle. Sprinkle the remaining onions over the potatoes, tucking them between rows if desired. Pour the remaining cheese sauce over the potatoes and spread into an even layer. Gently tap the baking dish against the counter to settle the sauce.
• Bake for 60 to 75 minutes. Bake uncovered until the top and edges are browned and crisp, and a knife inserted in the middle can easily slide through the potatoes, 60 to 75 minutes.
• Cool the gratin for 10 minutes before serving. Let the gratin cool for 10 minutes before scooping or slicing.

Steps:

• Preheat the oven to 350 degrees F. Spray a 2 quart, shallow flameproof baking dish with olive oil spray.
• Put the potatoes into a large pot and cover with water. Bring to a boil over medium heat. Reduce the heat and simmer until the potatoes are just tender, about 8 minutes. Drain and set aside to cool somewhat.
• Put the milk and flour into a large saucepan and whisk until the flour is dissolved. Add the garlic and thyme and heat over a medium-high heat, stirring constantly, until the mixture comes to a boil and is thickened, about 8 minutes. Remove from the heat, discard the thyme sprig, and stir in the salt. Add 1 cup of the cheese and stir until melted.
• Arrange half of the potatoes in the baking dish. Pour over half of the cheese sauce. Add the remaining potatoes and top with rest of the sauce. Sprinkle with the remaining cheese and bake for 25 minutes, until bubbling. Put under the broiler and broil on high until the top is browned, about 2 minutes. Serve hot.
• Serving size: about 1 cup