Potatoes Au Gratin Recipe

1. 1

   Preheat oven to 400°F. Lightly grease a 9x13x3” baking dish with butter, set aside.

Make the Cheese Sauce

1. 2

   Melt butter in a medium saucepan over medium heat.

2. 3

   Add flour, salt garlic powder and pepper and whisk to combine. Cook for about 1 minute, or until the roux bubbles and lightly browns.

   1 min
3. 4

   Whisk in milk and heavy cream.

4. 5

   Cook the sauce over medium heat, whisking often, until it has thickened (about 2-3 minutes).

   2 min
5. 6

   Once thickened, turn off the heat, stir in the cheese and whisk until melted. Set aside.

Assemble

1. 7

   Place ⅓ of the potatoes on the bottom of the prepared pan.

2. 8

   Top with half of the onion slices, then lightly sprinkle with salt and pepper.

3. 9

   Top onions with the another third of the potatoes, then top that layer of potatoes with the remaining onion slices and salt and pepper

4. 10

   Then, put the final third of the potatoes on top, and season with salt and pepper.

5. 11

   Next, pour the cheese sauce over the top of the potatoes.

Bake & Cool

1. 12

   Cover the baking dish with aluminum foil and bake in the preheated oven for 1 hour and 15 minutes.

   60 min
2. 13

   After 1 hour and 15 minutes, remove the foil and sprinkle the top with 1 cup of cheddar cheese.

3. 14

   Return the potatoes au gratin to the oven and bake, uncovered, for an additional 15 minutes. The cheese should melt and turn lightly golden brown, the filling should be bubbling, and the potatoes should be tender.

   15 min
4. 15

   Let cool and serve slightly warm.