1 yellow onion, thinly sliced
2 T. olive oil
2 T. butter
2 - 3 lbs. Yukon gold potatoes or russets
2 cups + 2 T. heavy cream
2 ½ cups grated Gruyere cheese or Grand Cru (10 oz.)
2 t. kosher salt Pepper to taste
¼ cup fresh minced parsley
Preheat oven to 350º. Butter 9 x 13-inch baking dish. If using russets, peel potatoes. Thinly slice the potatoes. Sauté onion in olive oil and butter or straight olive oil on medium-low heat for 15 minutes, until tender.
Mix potatoes in a large bowl with 2 cups cream and 2 cups cheese, salt and pepper. Add sautéed onion and mix. Pour the potato mixture into the baking dish. Pour the remaining cream over the top and sprinkle with the remaining cheese. Bake for 1 hour until the potatoes are tender and the top is browned. Maybe 1 hour and 15 minutes depending on your oven. Garnish with chopped parsley and allow to set for 10 minutes before serving.
If you want mushrooms: 2 cups mushrooms, sliced (optional) 2 T. butter, melted Coat the mushrooms with the melted butter and spread over the potatoes before adding the extra cream and cheese. From Crystal. They look, smell and taste divine.
