This gratin combines elegance with comforting flavours. Arrange thin slices of potatoes vertically in a baking dish and cook with leeks in a creamy mixture infused with garlic and thyme. This presentation adds visual appeal while emphasizing the contrast between the soft interior and the golden crust. It's a rich and satisfying side dish, perfect to serve alongside braised chicken thighs with rosemary and white wine for a complete meal.