Learn how easy it is to make Cheesy Scalloped Potatoes from scratch! This recipe has decadent caramelized onions in a creamy cheddar cheese sauce with simple seasonings. It’s make-ahead and Crock Pot friendly and the perfect side dish idea for friends and family.
Cheesy Scalloped Potatoes
I would love to add an extra emphasis on the word “cheesy” in this recipe. If you love your scalloped potatoes to be totally smothered in a creamy cheese sauce, without a single dry potato in the house, then this recipe is for you. Because the truth is, potatoes soak up a lot of sauce while they bake and even when they come out of the oven. This is a good thing, because that’s what makes them so flavorful. But you still want plenty of that delicious creamy cheese sauce left when you dig in or reheat!
There are some key things you need to know, especially when it comes to the best kinds of potatoes to use, how thin to slice them, make-ahead and Slow Cooker methods, and more- so read on!
How to Make It
See recipe card below this post for ingredient quantities and full instructions.
Prepare the Cheese Sauce:
Caramelize the onions in butter, olive oil, and thyme in a dutch oven over medium-low heat until light to dark brown. Remove and set aside.
Melt butter over medium heat. Add garlic and cook for 1 minute. Whisk in flour and cook 1-2 minutes, until raw flour smell is gone. Slowly incorporate milk, whisking as you do so. Bring to a boil, then remove from heat.
Add remaining seasonings. Let the roux cool down a bit. Reserve 1 heaping cup of cheese and gradually sprinkle in the rest, whisking continuously to incorporate. (Note: If the base is too hot when the cheese is added, the dairy will separate and the sauce will be grainy)
Stir in 2 TBS softened cream cheese, then add the caramelized onions.
Assemble and Bake:
Slice the potatoes: Peel the potatoes, rinse, and pat dry. Cut them into thin and even slices, about 1/8 inch thick. (See below this section for visual.)
Arrange half of the potatoes on the bottom of a lightly greased 9 x 13 baking dish and top with half of the cheese sauce.
Add remaining potatoes and remaining cheese sauce. Top with remaining cheddar cheese.
Bake: Cover and bake at 350° for 45 minutes. Remove cover and bake for 15 more minutes.
Broil at 450° for up to 5 minutes, until the top is slightly browned, watch it carefully. Let sit for 5 minutes, garnish with fresh parsley, and serve.
Best Potatoes for Scalloped Potatoes
- Yukon Gold Potatoes are ideal for making scalloped potatoes because they have the perfect amount of starch and absorbance. The starch keeps the cheese sauce nice and thick as it cooks, and their ability to absorb the flavors in the sauce makes each bite extra delicious. They are also firm enough where they hold up well during the baking process.
How Thin to Slice the Potatoes
- These potatoes will cook up perfectly in just 1 hour if sliced 1/8 inch thick.
- If your slices are too thick, and they won’t be cooked through so thin slices are important.
- A mandoline slicer makes this process quick and easy. I’ve linked to the one I use further down in this post.
- Assemble the potatoes as instructed and bake for 40 minutes at 350°. Let it cool completely. Cover and refrigerate for up to 3 days.
- When ready to serve, leave it covered and bake it at 350° for 35 minutes. If desired, remove the cover at the end and broil at 450° for up to 5 minutes to brown the top.
Slow Cooker Method
- Prepare sauce and slice the potatoes as outlined and layer them in a lightly greased Slow Cooker. Top with cheese.
- Heat on high for 4-5 hours or on low for 7-8.
- This recipe uses just cheddar, but a mixture of cheddar, gruyere, Parmesan, and mozzarella are all great choices.
- Russet potatoes make a good backup if you don’t have Yukon Golds.
- For a crunchy twist, add Crispy Fried Onions during the last 5 minutes of baking. (Don’t broil with those on top or they’ll burn.)
- Shred your own cheese from a block. Packaged cheese contains cellulose which prevents it from melting well. It also doesn’t taste as fresh or as flavorful. I love using Cracker Barrel Yellow Cheddar.
- Caramelized onions add a beautiful sweet offset to the cheddar in this recipe. If you’re pressed for time, you can simply soften them, or partially caramelize them.
Store in an airtight container and refrigerate for up to 3 days or freeze for up to 3 months.
Scalloped Potatoes vs. Au Gratin Potatoes
Scalloped Potatoes: Made with a roux of butter, flour, + milk. Some also contain cheese, but there are many versions without any cheese at all. (You know where I stand on that 😁.)
Potatoes Au Gratin: Made with cream, butter, + cheese. Often times it’s also topped with breadcrumbs. The potatoes are often very thinly sliced as well, while scalloped potatoes may be cut slightly thicker.
“Gratin” means “a dish with a light browned crust of breadcrumbs or melted cheese”
For more info, check out this resource from TheKitchn.
What to Serve This With
- Roast Chicken
- Chicken Milanese
- Copycat Longhorn Parmesan Crusted Chicken
- Fried Chicken Tenders
- Hamburger Steak
- Chicken Fried Steak
- Steak w/ Copycat Texas Roadhouse Steak Rub
Tools For This Recipe
(Amazon affiliate links)- Check out all of my kitchen essentials here.
- Mandoline– Makes it super easy to slice potatoes, onions, carrots, cucumbers, etc.
- Long Chefs Knife– An alternative to a mandoline slicer. I have this knife, it’s affordable but works really well.
- 9 x 13 casserole dish– This is the one I use and that is pictured in this recipe.
- Box Cheese Grater– Always shred your own cheese. It melts much better and tastes much more flavorful.
- Dutch Oven– Perfect for caramelizing onions and preparing the cheese sauce as it conducts heat very well and the surface isn’t prone to sticking or staining.
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Cheesy Scalloped Potatoes
- 6 tablespoons butter, separated
- 1 Tablespoon olive oil
- 1 large yellow onion
- ½ teaspoon dried thyme
- 2 cloves garlic
- 4 tablespoons flour
- 3 cups milk
- 3 ½ cups shredded orange cheddar cheese, divided
- 2 Tablespoons cream cheese, softened
- ½ teaspoon mustard powder
- ½ teaspoon salt
- ¼ teaspoon pepper
- 1 pinch cayenne pepper
- 2.5 lbs. Yukon Gold Potatoes, about 6 medium potatoes
- Preheat oven to 350.
- Measure out the milk, the shredded cheese, and the cream cheese. Set aside to allow them to come down to room temperature, they shouldn’t be cold when added to the sauce.
- Soften/Caramelize the Onions: Melt 2 TBS butter and heat 1 TBS olive oil in a large skillet or dutch oven over medium-low heat. Cut the onions into ¼ inch strings and add them to the pot along with ½ tsp dried thyme. Let them caramelize slowly until they turn a soft brown color, you’ll notice the butter will eventually begin to foam, this is a good sign. (See post for visual.) Let them cook slowly for about 25 minutes, until they’re nice and brown. Once done, remove and set aside.
- Combined Butter & Flour: Increase heat to medium. Add 4 TBS butter to the pot along with the garlic. Cook for 1 minute and use a silicone spatula to “clean” the bottom and sides of the pot. Add 1 TBS flour at a time (4 total) and whisk to incorporate. Continue to whisk for 1 minute or until you can no longer smell flour.
- Add the Milk: Gradually add the milk, splashes at a time, and whisk to incorporate. If you add it too fast the roux will thin out too much. Bring to a boil, then remove from heat.
- Add Seasonings: Add ½ teaspoon mustard powder, ½ teaspoon salt, ¼ tsp pepper, and a pinch of cayenne. Stir to combine.
- Add Cheese: Let the roux cool down a bit. Reserve 1 heaping cup of cheddar cheese and gradually sprinkle the rest in. If the base is too hot when the cheese is added, the dairy will separate and the sauce will be grainy
- Stir in 2 TBS cream cheese, then add the caramelized onions.
- Slice the potatoes: Peel the potatoes, rinse, and pat dry. Cut them into thin and even slices, about 1/8 inch thick. (See post for visual.)
- Fill the Casserole Dish: Arrange half of them on the bottom of a lightly greased 9 x 13 baking dish and top with half of the cheese sauce. Add remaining potatoes and remaining cheese sauce. Top with remaining cheddar cheese.
- Bake: Cover and bake at 350 for 45 minutes. Remove cover and bake for 15 more minutes.
- Broil at 450 for up to 5 minutes, until the top is slightly browned, watch it carefully. Let sit for 5 minutes, garnish with fresh parsley, and serve.
Shred the cheese from a block, packaged cheese contains cellulose which doesn’t allow it to melt as well. It also doesn’t taste as fresh.
Instead of using all cheddar, you can also use gruyere which pairs nicely with the caramelized onions. Mozzarella and Parmesan are good additions as well.
This recipe makes a lot of sauce, but the potatoes absorb a lot of the sauce as they bake and even after they come out of the oven, so this ensure that they remain nice and cheesy. Especially if you have leftovers.
Tools For This Recipe: (Amazon affiliate links)- Check out all of my kitchen essentials here.
- Mandoline- Makes it super easy to slice potatoes, onions, carrots, cucumbers, etc.
- Long Chefs Knife- An alternative to a mandoline slicer. I have this knife, it's affordable but works really well.
- 9 x 13 casserole dish- This is the one I use and that is pictured in this recipe.
- Box Cheese Grater- Always shred your own cheese. It melts much better and tastes much more flavorful.
- Dutch Oven- Perfect for caramelizing onions and preparing the cheese sauce as it conducts heat very well and the surface isn't prone to sticking or staining.