Description
These Caramelized Onion Scalloped Potatoes take a beloved comfort food to an entirely new level. Thinly sliced Yukon Gold potatoes are tossed with nutty Gruyère and sharp Parmesan, then baked over a sweet, buttery layer of deeply caramelized onions. The result is a savory, rich, and utterly luxurious side dish with a creamy texture and an irresistible golden-brown crust, making it the perfect accompaniment to any holiday feast or Sunday dinner.
Ingredients
For the Caramelized Onion Scalloped Potatoes
- 2 tablespoons extra virgin olive oil, divided
- 4 cups thinly sliced onions, sliced crosswise
- 6 medium Yukon gold potatoes (about 1 1/2 pounds), peeled and sliced 1/8 inch thick
- 3/4 cup grated Gruyère cheese, divided
- 1/2 cup grated Parmesan cheese
- 1 teaspoon kosher salt
- 1/2 teaspoon white pepper (or black pepper if that is what you have)
- 1 teaspoon butter, for greasing the baking dish
- 1/3 cup stock (chicken, beef, or vegetable)
- 1 teaspoon finely minced fresh rosemary
Instructions
Step 1: Preheat the Oven
Set your oven to 400°F.
Step 2: Caramelize the Onions
Heat 1 tablespoon of olive oil on medium-high heat in a heavy-bottomed sauté pan. Add the 4 cups of thinly sliced onions and stir until they are coated in the oil. Cook them for approximately 15 to 20 minutes, stirring frequently, until they are soft and have achieved a deep golden-brown, caramelized color.
Step 3: Toss the Potatoes and Cheese
Put the 6 medium peeled and 1/8-inch thick sliced potatoes in a large bowl. Gently toss them with the remaining 1 tablespoon of olive oil, 1/2 cup of grated Gruyère cheese, 1/2 cup of grated Parmesan, 1 teaspoon of kosher salt, and 1/2 teaspoon of white pepper. Pro Tip: This step is crucial for preventing the starch in the potato slices from oxidizing and turning grey.
Step 4: Layer the Casserole
Lightly grease a large gratin dish (2 to 3-quart capacity) or a 9 x 13-inch casserole with 1 teaspoon of butter. Place the fully caramelized onions in a smooth, even layer across the bottom of the prepared dish. Next, arrange the sliced, cheese-coated potatoes in an appealing pattern over the onions.
Step 5: Add Stock and Cheese
Pour the 1/3 cup of stock (chicken, beef, or vegetable) evenly over the arranged potatoes. Sprinkle the top with the remaining 1/4 cup of grated Gruyère cheese.
Step 6: Bake Covered
Cover the entire casserole dish tightly with aluminum foil and bake for 50 minutes at 400°F, or until the potatoes are fork tender.
Step 7: Broil to Finish
Carefully remove the aluminum foil. Place the uncovered dish under the broiler for about 5 minutes, or until the top is lightly browned and bubbly. Watch closely!
Step 8: Serve
Remove from the oven and sprinkle the hot potatoes with 1 teaspoon of finely minced fresh rosemary just before serving.
Notes
Even Slicing is Key: To ensure all potatoes cook evenly and have a consistent creamy texture, it’s vital to slice them uniformly, ideally about 1/8 inch thick. A mandoline slicer is highly recommended for this.
Make-Ahead Instructions: This dish can be prepped up to 24 hours in advance! Complete steps 1-5 (caramelizing, tossing, layering, and adding stock/cheese), cover tightly, and refrigerate. Remove from the fridge while the oven preheats, then proceed with the covered bake.
Cheese Substitutions: If Gruyère is unavailable, Swiss cheese is the closest substitute in terms of flavor and meltiness. You can also increase the stock to 2/3 cup and use heavy cream instead for a richer dish.
- Prep Time: 25 minutes
- Cook Time: 55 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1/8 of recipe
- Calories: 227
- Sugar: 4g
- Sodium: 410mg
- Fat: 14g
- Saturated Fat: 7g
- Unsaturated Fat: 7g
- Trans Fat: 0g
- Carbohydrates: 19g
- Fiber: 2g
- Protein: 7g
- Cholesterol: 22mg
Keywords: caramelized onion scalloped potatoes, gruyere potato casserole, au gratin potatoes, holiday side dish, creamy potato recipe, make-ahead potatoes