How to Make Melt in Your Mouth Scalloped Potatoes .
- Preheat oven to 350 degrees F.
- Lightly grease a 9×13 or a deep 9×9 baking dish.
- Add olive oil and butter to a medium skillet and heat over medium heat. Add the onions, salt and pepper, to taste. Cook over medium heat, stirring occasionally until onions are transparent in color.
- Sprinkle flour on top of cooked onion mixture and whisk to form a roux. Cook for 2 minutes.
- Slowly add the milk, whisking constantly. Bring roux to a simmer and let thicken just slightly, about 2 to 3 minutes after coming to a simmer. Remove from heat and set aside.
- Layer half of the potatoes, half the cheese, and half the onion sauce, in the prepared baking dish. Repeat with second layer.
- Cover baking dish with foil and bake for 1 hour. Remove foil and bak an additional 30-40 minutes or until potatoes are easily pierced with a fork. Broil the top for 2-3 minutes to brown up the cheese. Remove from oven and let cool 10 minutes before serving.
