Description
Layers of tender potatoes and caramelized onions smothered in a creamy cheese sauce—comforting, savory, and effortless to make.
Ingredients
4 cups potatoes, thinly sliced (Yukon Gold or Russet)
2 Tbsp unsalted butter
2 Tbsp olive oil
2 large yellow onions, thinly sliced
2 cloves garlic, minced
2 tsp fresh thyme leaves (or 1 tsp dried thyme)
1 Tbsp all-purpose flour
1 cup whole milk
1 cup heavy cream
1 cup shredded Gruyère or Swiss cheese, divided
¼ cup grated Parmesan cheese
Salt and freshly ground black pepper, to taste
Instructions
Preheat oven to 375 °F (190 °C). Lightly grease a 9×9‑inch baking dish and set aside.
In a large skillet over medium heat, melt butter with olive oil. Add onions and cook 12–15 minutes until deep golden and caramelized, stirring occasionally. Stir in garlic and thyme; cook 1 minute more.
Sprinkle flour over onion mixture and stir, cooking 1 minute to remove raw flour taste. Gradually whisk in milk and cream, stirring until smooth and slightly thickened—about 2–3 minutes. Season with salt and pepper.
Arrange half the potato slices in an even layer in the prepared dish. Pour half the onion‑cream sauce over them, then sprinkle with half the Gruyère.
Repeat with remaining potatoes, sauce, and Gruyère. Finish by sprinkling Parmesan on top.
Cover with foil and bake for 30 minutes. Remove foil and bake an additional 20–25 minutes until potatoes are tender and top is bubbling and golden.
Let rest 5–10 minutes before serving to allow the sauce to set slightly.
- Prep Time: 15 minutes
- Cook Time: 50 minutes
- Category: Main Course
