Step-by-Step Instructions
Preparing the Potatoes
Preheat the Oven: Begin by preheating your oven to 375°F (190°C). This will ensure it reaches the right temperature while you prepare the rest of the dish.
Slice the Potatoes: Using a sharp knife or mandoline slicer, slice your potatoes into thin, even rounds, about 1/8 inch thick. Uniform slices are crucial for even cooking.
Soak the Potatoes: To remove excess starch and prevent the potatoes from sticking together, soak the slices in a bowl of cold water for about 30 minutes. Drain and pat them dry with a paper towel.
Making the Creamy Sauce
Cook the Aromatics: In a saucepan, melt 2 tablespoons of butter over medium heat. Add finely chopped garlic and onion, cooking until they become soft and fragrant, about 2-3 minutes.
Prepare the Roux: Stir in 2 tablespoons of flour and cook for 1 minute to form a roux. This will help thicken the sauce.
Add Dairy: Gradually whisk in 1 cup of heavy cream and 1 cup of milk. Continue to cook, stirring constantly, until the sauce thickens and starts to bubble. Season with salt and pepper to taste.
Incorporate Cheese: Remove the saucepan from heat and stir in 1 ½ cups of grated cheddar cheese until fully melted and smooth.
Assembling the Dish
Layer the Potatoes: Grease your baking dish with butter or non-stick spray. Arrange a layer of potato slices in the bottom of the dish, slightly overlapping them.
Add Sauce: Pour a portion of the cheese sauce over the potato layer, ensuring it’s evenly distributed.
Repeat Layers: Continue layering the potatoes and sauce until you’ve used all the potatoes and sauce, finishing with a layer of sauce on top.
Dot with Butter: For an extra touch of flavor and a crispy top, dot the top layer of sauce with small pieces of butter.
Baking
Cover and Bake: Cover the baking dish with aluminum foil and bake in the preheated oven for 45 minutes.
Uncover and Continue Baking: Remove the foil and bake for an additional 30 minutes, or until the potatoes are tender and the top is golden brown and bubbly.
Cool and Serve: Allow the scalloped potatoes to cool for a few minutes before serving. This helps the sauce set and makes serving easier.
