Ingredients

  • 2 tablespoons unsalted butter
  • 1 medium onion, minced (about 1 cup)
  • 2 cloves garlic, minced or pressed through garlic press (about 2 teaspoons)
  • 1 tablespoon chopped fresh thyme leave
  • 1 1/4 teaspoons salt
  • 1/4 teaspoon ground black pepper
  • 2 1/2 lbs russet potatoes, peeled and sliced 1/8 inch thick (about 5 medium)
  • 1 cup low-sodium chicken stock
  • 1 cup heavy cream
  • 2 bay leaves
  • 4 ounces cheddar cheese, shredded (1 cup)

Method

  • Heatoven to 425 degrees.
  • Melt butter in large Dutch oven over medium-high heat until foaming subsides.
  • Add onion and cook, stirring occasionally, until soft and lightly browned, about 4 minutes.
  • Add garlic, thyme, salt, and pepper; cook until fragrant, about 30 seconds.
  • Add potatoes, chicken broth, cream, and bay leaves and bring to simmer.
  • Cover, reduce heat to medium-low, and simmer until potatoes are almost tender (paring knife can be slipped into and out of potato slice with some resistance), about 10 minutes.
  • Discard bay leaves.
  • Transfer mixture to 8-inch-square baking dish (or other 11/2-quart gratin dish); sprinkle evenly with cheese.
  • Bake until cream is bubbling around edges and top is golden brown, about 15 minutes.
  • Cool 10 minutes before serving.