Creamy Gruyère and Caramelized Onion Scalloped Potatoes
Ingredients:
3 lbs (1.4 kg) potatoes, thinly sliced (Russet or Yukon Gold work well)
2 large onions, thinly sliced
2 tbsp unsalted butter
1/4 cup all-purpose flour
1 1/2 cups heavy cream
1 1/2 cups grated Gruyère cheese
1/2 cup grated Parmesan cheese
Salt and black pepper to taste
Fresh thyme leaves for garnish (optional)
Instructions:
Caramelize the Onions:
In a large skillet, melt butter over medium heat. Add sliced onions and cook, stirring occasionally, until they’re deep golden brown and caramelized (about 30-40 minutes). Season with salt and pepper.
Preheat Oven:
Preheat your oven to 375°F (190°C).
Make the Cream Sauce:
In a saucepan, melt butter over medium heat. Whisk in flour to make a roux, cooking for 1 minute. Gradually whisk in heavy cream, and cook until the sauce thickens. Remove from heat and stir in Gruyère and Parmesan cheese until melted and smooth. Season with salt and pepper.
Assemble:
In a greased 9×13-inch baking dish, create a layer of overlapping potato slices. Top with a portion of caramelized onions and cream sauce. Repeat the layers, finishing with a layer of cream sauce and Gruyère cheese on top.
Bake:
Cover with foil and bake for 45 minutes. Remove the foil and bake for an additional 30-40 minutes, or until the potatoes are tender and the top is golden brown.
Serve:
Let it rest for a few minutes before serving. Garnish with fresh thyme leaves if desired.