Potato, Leek, Gruyere, And Oyster Mushroom Gratin

Total Time: 2 hrs 15 mins Preparation Time: 45 mins Cook Time: 1 hr 30 mins

Ingredients

• Servings: 10
• 4 tablespoons butter
• 1 lb oyster mushroom, halved if large
• 1 tablespoon garlic, minced
• 4 cups leeks ( and pale green parts only, about 4 large, thinly sliced)
• 1 tablespoon fresh thyme, minced
• 1 3/4 cups chicken broth
• 1 3/4 cups whipping cream
• 1/4 cup dry wine
• 1 teaspoon salt
• 1/2 teaspoon black pepper
• 3 3/4 lbs russet potatoes, peeled, thinly sliced into rounds (about 8 cups)
• 2 1/2 cups gruyere cheese, grated (about 10 ounces)

Recipe

• 1 melt 2 tablespoons butter in heavy large skillet over medium-high heat. add mushrooms and sauté until almost tender, about 5 minutes. add garlic and sauté until mushrooms are tender and golden, about 3 minutes longer.
• 2 transfer mushroom mixture to bowl. melt remaining 2 tablespoons butter in same skillet over medium-high heat. add leeks and thyme and sauté until leeks are tender and beginning to brown, about 8 minutes.
• 3 add leek mixture to bowl with mushrooms. (can be made 1 day ahead. cover and refrigerate.).
• 4 preheat oven to 400°f butter 13x9x2-inch baking dish. whisk broth, cream, wine, 1 teaspoon salt and 1/2 teaspoon pepper in large bowl to blend.
• 5 layer 1/3 of potatoes on bottom of prepared dish. top with half of mushroom-leek mixture, then 3/4 cup cheese. top with half of remaining potatoes.
• 6 pour half of cream mixture over. top with remaining mushroom-leek mixture and 3/4 cup cheese.
• 7 cover with remaining potatoes. pour remaining cream mixture over; sprinkle with remaining cheese.
• 8 bake gratin uncovered until potatoes are tender and sauce bubbles thickly, about 1 hour 20 minutes. let gratin stand 30 minutes before serving.