French Onion Potato Gratin

Ingredients:

• 2/3 cup milk
• 2/3 cup heavy cream
• 2 tablespoons butter, softened
• 1 pound Idaho® Yellow potatoes
• 1 pound onions, sweet or vidalia, peeled, thinly sliced
• 4 thyme sprigs, picked and chopped
• 4 ounces Gruyere cheese, shredded
• 2 garlic cloves, smashed
• 1 ounce brandy or calvados
• 3 ounces olive oil
• 2 teaspoons Kosher salt
• 1/4 teaspoon black pepper
• 4 pounds Idaho® Fingerling potatoes, mixed colors, thinly sliced, blanched, patted dry

Directions:

1. In a large skillet or rondeau, over medium high heat, add butter and 1 ounce oil. To melted butter add julienned onions, and 1 teaspoon salt. Cook slowly, stirring until onions are caramelized to golden brown, about 30 minutes. Add brandy and let the liquid cook off. Remove from heat and stir in chopped thyme. Reserve for later.
2. Preheat oven to 400°F. In a wide pot over medium heat, add milk, cream, and smashed garlic. Slowly heat while stirring occasionally.
3. Peel potatoes, slice 1/8 inch thick. Place sliced potatoes in milk mixture and bring to a simmer while gently stirring. The starch in the potatoes will start to thicken the milk mixture. Add 1 teaspoon of salt and the black pepper. Adjust seasoning if desired. Cook potatoes until just tender, about 15-20 minutes. Remove from heat and fold in onions.
4. Butter the sides and bottom of four 6-inch wide by 2-inch deep pie dishes. Divide the potato onion mixture evenly amongst the four dishes. Sprinkle each with an ounce of the gruyere cheese. Add some of the milk from the potatoes.
5. Arrange the sliced fingerlings in a circular pattern on top of the cheese in alternating colors. Brush with melted butter being careful to preserve the arrangement.
6. Bake at 400°F 30-40 minutes, until the top is lightly browned and the cream is starting to bubble up at the sides. Sprinkle with flaky salt and serve.