These Fried Onion Scalloped Potatoes are slices of russet potatoes smothered in a creamy cheese sauce, and topped with crispy, golden-fried onions. They are my scalloped potatoes with an added crunch and extra flavor from the fried onions. I plan to add these to my Thanksgiving menu (do you know what day Thanksgiving is this year?) to impress my guests and prove that fried onions are not just for green bean casserole anymore!
Crispy Onion Scalloped Potatoes Ingredients & Substitutions
- Potatoes: I used russet potatoes for this recipe because their starch helps thicken the sauce and ensures the potatoes bake fork-tender. Yukon gold potatoes would also work well. Just be sure to wash the potatoes before peeling and slicing.
- Cheese Sauce: The creamy, cheesy sauce coats the potatoes beautifully (and deliciously, I might add)! It is made with unsalted butter, flour, kosher salt, pepper, whole milk, and cheese. If using salted butter, you may want to lessen the salt in the recipe.
- Milk: I recommend using whole milk for this recipe. If you use milk with less fat, like 1% or skim, the sauce might curdle. Also, make sure the milk is at room temperature before you add it to the sauce.
- Cheese: Yes, I added cheese to the cream sauce, so these could technically be considered au gratin potatoes. But, no matter what you call them, I love the cheesiness of the sauce. Some cheese is added to the sauce, the rest is sprinkled over the top. I like sharp cheddar cheese for the most pronounced flavor. But, you could use other kinds of cheese like Gruyere (check out my Gruyere Scalloped Potatoes), Monterey Jack, Gouda, or a combination of your favorite cheeses.
- Fried Onions: I like frying yellow onions because they’re naturally sweet and get nice and crispy and golden brown. (I used them on my French Onion Funeral Potatoes, too.) White onions work too, but they have a stronger taste. For a sweeter onion, try Vidalia or Walla Walla onions.
- Oil: Vegetable or canola oil are both good choices for frying. It has a neutral flavor and a high melting point. Once you have fried the onions, don’t let the oil go to waste–check out how to clean used cooking oil!
Slicing the Potatoes {Tips for Uniform Potato Rounds}
It is important to lay out the potato slices perfectly straight, which makes it look beautiful and helps the dish cook evenly. I highly recommend using a mandoline slicer (affiliate link) for uniform slices. Your mandoline should have a “thin slice” blade, especially for this dish. Use your mandoline right on the cutting board. (Using it over a bowl will cause the potatoes to separate and they will not be lined up as they are in this recipe.) I cut one potato at a time and set it aside while I worked on the next one.
Can I Use Store-Bought Crispy Fried Onions?
Yes, you can use store-bought crispy fried onions to save time, but I really encourage you to make the fried onions yourself! They add more flavor and give the scalloped potatoes a personal touch. If you prefer, you can also add crispy onion rings on top just before serving–that will definitely get people talking!
Storing & Reheating Fried Onion Scalloped Potatoes
Don’t let any of these cheesy potatoes go to waste! Here is how to store and reheat leftovers:
To Store: To store fried onion scalloped potatoes, first, let them cool to room temperature. Then, store them in an airtight container in the refrigerator. (It is okay to store them with the fried onions, but they may lose some of their crispiness.) The potatoes will last up to 3-4 days. For longer storage, freeze the potatoes.
To Reheat: Reheat the potatoes in the oven for a few minutes at 350°F–this will help crisp up the fried onions. Or, warm up the potatoes in the microwave.
Freezing Fried Onion Scalloped Potatoes
If you are not going to enjoy the fried onion scalloped potatoes within a few days, freeze them! I do recommend freezing just the cheesy potatoes, not the fried onions (but you can). It’s easy to add those when serving. To freeze, first let the potatoes cool completely. Next, store them in a freezer-safe container. I like to freeze the potatoes in individual containers. Label and date the container(s); they will last up to 2 months. Let the potatoes thaw in the refrigerator overnight before reheating and adding the fried onions.
Fried Onion Scalloped Potatoes
Ingredients
Potatoes
- 3 pounds (approximately 8-10 medium) russet potatoes, rinsed, peeled, and thinly sliced with a mandoline
- 6 tablespoons unsalted butter
- ½ cup (62.5 g) all-purpose flour
- 2 teaspoons kosher salt
- ½ teaspoon black pepper
- 3 cups (735 g) whole milk, room temperature
- 2 cups (226 g) sharp cheddar cheese, shredded, divided
Fried Onions
- 2 large yellow onions, thinly sliced, layers separated (about 4 cups onions)
- 4 cups (32 ounces) vegetable oil
- 1 teaspoon kosher salt
- parsley, for garnish
Instructions
- Preheat oven to 375°F. Spray a 9×13-inch baking dish with cooking spray. Set aside.
- In a medium saucepan over medium heat, melt butter. Whisk in the flour, salt, and pepper. Cook for 1 minute.
- Slowly drizzle in milk, whisking constantly. Continue cooking until the mixture thickens, 5-8 minutes, whisking frequently.
- Remove from heat. Stir in 1 cup of cheese. Continue stirring until the cheese is melted and smooth, about 30 to 60 seconds. Set aside.
- Carefully set the potato slices in the bottom of the prepared baking dish (trying to keep the shape of the potato together), and fan them out in a single layer.
- Top the potatoes with the cheese sauce and the remaining cup of shredded cheese.
- Cover with aluminum foil and bake for 50 minutes.
- After 50 minutes, remove foil and continue to bake for an additional 10 minutes, or until potatoes are fork-tender.
- While the potatoes are baking, prepare the fried onions.
Fried Onions
- Line a large baking sheet with two layers of paper towels. Set aside.
- To a large saucepan over high heat, add oil. Heat to 350°F.
- Working in batches, add about 1 cup of onions to the hot oil. Cook until onions turn pale golden brown, about 2-5 minutes. Using a fine mesh strainer or slotted spoon, carefully remove the fried onions from the hot oil. Place them in an even layer onto the prepared baking sheet. Set aside and repeat with the remaining onions. (Make sure the oil temperature is at 350°F before each batch.) Sprinkle fried onions with salt.
- Sprinkle the fried onions evenly over the top of the scalloped potatoes.
- Serve hot, garnished with parsley. Add salt and pepper to taste.
Did you make this recipe?
You can tag me at @iamhomesteader.
What the Test Kitchen had to say about this recipe:
Autumn
Wow! These are fantastic! Every time I went out to the kitchen, I ate more! I am definitely serving these this holiday season!
Elizabeth
These are the perfect scalloped (or au gratin, if you are getting picky) potatoes! Absolutely perfect with the crunchy fried onions!
Annabelle
These will for sure be a hit during the holidays. Worth the effort to fry your own onions.
Bella
Love the layers of potatoes and cheese! The fried onions add a nice touch of crunch and extra flavor.
Selena
A hearty and satisfying dish. The combination of creamy cheese and crispy fried onions makes it a standout. It’s rich and indulgent, perfect for a special occasion.
10/10!!! I thought this was going to take a lot of time but it wasn’t bad. BUT THOSE CRISPY FRIED ONIONS ARE CHANGING MY LIFE I WANT THEM ON EVERYTHING. When i put them on this scalloped potato recipe I literally moaned they are so good. This is the best scalloped potato recipe I have ever had, hands down