I have made many different potato gratins in my day and they have never worked out right for me, until this recipe. For some reason it all came together and the flavor was wonderful! The recipe came from the December 2010 Bon Appetit. I am glad I saved it and that I prepared it. They called for the recipe to be prepared in a 9 inch glass pie dish, I chose to bake mine in a 12x6x2 inch glass dish.
Potato Gratin with Gruyere
3/4 cup plus 2 Tbsp. heavy whipping cream
1 large garlic clove, peeled and slightly smashed
1 1/4 lbs. russet potatoes, peeled, cut into 1/8-inch thick rounds
1 1/2 tsp. chopped fresh thyme
1/4 cup whole milk
1/2 cup coarsley grated Gruyere cheese
Position rack in center of oven and preheat to 350. Generously butter 9-inch glass pie dish. Place on a rimmed baking sheet. Combine garlic and cream in small saucepan and bring to simmer over low heat. Cover and remove from heat.
Arrange 1/3 of potato rounds, slightly overlapping, in concentric circles in prepared dish; sprinkle with 1/2 teaspoon of thyme and season lightly with salt and pepper. Pour 1/4 cup garlic cream over. Repeat layering 2 more times with remaining potato, thyme, salt, pepper and garlic cream. Pour remaining garlic cream over, then whole milk. Sprinkle with cheese.
Bake until golden brown and potatoes are very tender, 1 hour to 1 hour and 10 minutes. Let rest 10 minutes before serving.