Easy Cheesy Scalloped Potatoes Recipe (with Video)

Preparation
1. Pre-heat oven to 350F (conventional) and brush butter in a casserole pan or baking dish of choice (I used a 7x11" oval pan).
Prepare the white sauce
1. Melt the butter in a nonstick saucepan over medium low heat.
2. Add the flour and stir for 1 minute.
3. Then add the minced garlic and spices and stir for another minute.
4. Add the milk and stir to combine, and then mix in the cheeses until they melt.
5. Do not cook too long or thicken the sauce as it will thicken during baking.
6. If the sauce is too thick, adjust the consistency by adding more milk.
7. Taste and adjust the seasoning.
Prepare the onions
1. Thinly slice the onion and caramelize it in the olive oil until it is soft and golden.
Prepare the potatoes
1. Wash and thinly slice the potatoes into 3mm or ⅛" thick slices, preferably using a mandolin.
Assemble the dish
1. Add 1 cup of the sauce to the bottom of the dish and spread it out.
2. Then either layer the potatoes horizontally with sauce between each layer, or stack them vertically and pour the sauce on top.
3. Add the caramelized onions and cover them with the remaining sauce.
Bake the dish
1. Bake until the potatoes are tender. This can take between 45-60 minutes depending on the type of potatoes you're using and how wide your baking pan is.
2. Check with a fork for doneness.
3. Once the potatoes are tender, sprinkle over more cheese and place back in the oven on the broil setting for 3-5 minutes until the cheese has melted.
Garnish and serve
1. Garnish with chopped parsley.
2. Serve and enjoy.