There are scalloped potatoes, the kind that is so addictive, you can eat maybe half the pan in one sitting, because at that moment, meat becomes overrated. Once layered, pour cream until the potatoes are covered then top with even more cheese. Traditionally, scalloped potatoes are baked with no cheese, in a cream sauce, most often made with raw flour in the sauce that thickens up as it bakes.
Using a mandoline ensures each potato is thinly sliced to the same consistency. Otherwise, they may unevenly bake in the oven. Peel and slice potatoes to between 1/8- and 1/4-inch-thick for the best results and even cooking. Use a mandolin for even slicing if you have one.
Starchy potatoes work best for scalloped potatoes. The starch content helps the cream to thicken up and create a perfect creamy sauce during the cooking process. The ingredients for garlic parmesan gratin potatoes are potatoes, cheese, and heavy cream with additional flavors such as garlic and thyme.
- 1 1/4 lbs red potatoes, washed
- 1 onion, sliced thinly
- 3 Tbsp butter
- 3 Tbsp all-purpose flour
- 2 cloves garlic, minced
- 1 tsp dry mustard
- 1/4 tsp dried thyme
- 1/4 tsp paprika
- Salt and pepper, to taste
- 2 cups whole milk
- 1 cup cheddar cheese shredded
- 1/2 cup gruyere cheese shredded
- 1/4 cup Parmesan cheese grated
- Fresh parsley, for garnish
- Additional 1/4 cup cheddar cheese, shredded
- Additional 2 Tbsp Parmesan cheese, grated
- preheat oven to 400 degrees F. Butter a 2-quart casserole dish and set aside.
- Slice potatoes in 1/8″ thin slices (I use this mandoline slicer), and set aside.
- Add butter to medium saucepan, and heat over medium heat. When butter is melted, add garlic and saute for 1 minute, until fragrant. Add flour, whisk, and cook 1 minute.
- Slowly add milk, whisking continuously, until no lumps remain. Whisk over medium heat until mixture is thick and coats the back of a spoon.
- Turn off heat, add cheeses, dry mustard, thyme, paprika, salt and pepper, and stir until smooth.
- Layer half the potatoes and onion slices in the prepared casserole dish, pour approximately half of the cheese sauce over potatoes and let sit for a minute. Repeat with remaining potatoes, onions, and cheese sauce.
- Sprinkle top of potatoes with gruyere, cheddar, and Parmesan. Spray aluminum foil with cooking spray, then cover the casserole dish. Place casserole on a baking sheet and bake for 60 minutes.
- Remove foil and bake uncovered an additional 25-30 minutes. Potatoes should be tender and cheese melted.
- Broil on high for a minute or two for extra browning and crispiness.
- Sprinkle top with chives and parsley and serve.