Potato and Onion Gratin is a classic, comforting dish that layers thinly sliced potatoes and sweet onions in a creamy, cheesy sauce. Baked to golden perfection, this gratin features tender potatoes and caramelized onions with a rich, velvety cream infused with garlic and herbs. It’s the perfect side dish for holiday gatherings, Sunday roasts, or a cozy family dinner. The top layer becomes deliciously crispy while the inside remains creamy and flavorful, making each bite a combination of textures and flavors that’s both satisfying and indulgent.
Ingredients:
- 2 lbs potatoes (Yukon Gold or Russet), thinly sliced
- 1 large onion, thinly sliced
- 2 garlic cloves, minced
- 1 1/2 cups heavy cream
- 1 cup whole milk
- 1 cup shredded Gruyère or cheddar cheese
- 1 teaspoon fresh thyme (or 1/2 teaspoon dried thyme)
- Salt and pepper to taste
- 2 tablespoons unsalted butter, for greasing the dish
- 1/4 cup Parmesan cheese, grated (for topping)
Instructions:
- Preheat the oven: Preheat your oven to 375°F (190°C). Grease a 9×13-inch baking dish with butter.
- Prepare the cream mixture: In a saucepan over medium heat, combine the heavy cream, milk, garlic, and thyme. Heat gently until the mixture is warm and the garlic is fragrant, but do not let it boil. Season with salt and pepper, then remove from heat.
- Layer the potatoes and onions: In the greased baking dish, arrange half of the potato slices in an even layer. Top with half of the sliced onions. Sprinkle half of the shredded cheese over the layer. Repeat with the remaining potatoes, onions, and cheese.
- Pour the cream: Pour the warm cream mixture evenly over the layered potatoes and onions. Gently press down on the layers to ensure they are fully coated with the cream.
- Bake: Cover the dish with foil and bake for 45 minutes. After 45 minutes, remove the foil, sprinkle the top with grated Parmesan cheese, and bake uncovered for another 20-25 minutes, or until the potatoes are tender and the top is golden brown and bubbly.
- Rest and serve: Let the gratin cool for 10 minutes before serving, allowing the creamy sauce to set.
This Potato and Onion Gratin is rich, creamy, and full of flavor, making it the ultimate side dish for any special meal. The combination of tender potatoes, sweet onions, and melted cheese is simply irresistible!
