Cheesy Scalloped Potatoes with Caramelized Onions, the ultimate holiday side dish. These potatoes are creamy, cheesy, and seasoned simply for a potato casserole that everyone really loves. The thinly sliced potatoes melt into a creamy, cheesy sauce. The top brown up in the oven adding a bit of crunch. Together these creamy crunchy potatoes are so delicious. They’re simple to make and always a crowd favorite.
Here are the details…
Before I slice the potatoes, I always caramelize the onions. A lot of potato casseroles call for onion powder. But I wanted to add a little more of a fresh onion flavor that wasn’t over powering, but just right.
I love to use caramelized onions for an onion flavor that’s more mellow.
I caramelize them down in a bit of butter and add wine to help them caramelize a little faster. Then just a little fresh thyme, salt, and pepper.
While the onions are cooking, I mix the cream, milk, and the two types of cheese together. Most scalloped or au gratin recipes will call for you to cook the milk and cheese together on the stove, creating more of a cheese sauce.
I’ve found that the cheese sauce didn’t help the potatoes cook. It left me with a drier potato, and not in a delicious way.
So, I skip cooking the sauce.
Slice the potatoes using a super sharp knife or a mandoline. Using a mandoline is ideal as you’ll get even slices and it’s much quicker too.
Layer the potatoes in a baking dish with the cream/milk/cheese mix and onions. I layer this up similar to a lasagna to ensure every potato gets evenly seasoned.
Once assembled, you bake…
The baking time for these potatoes is long. I cook mine a full two + hours to ensure that the potatoes are really cooked and turn tender. I then remove the foil, add a little more cheese, and bake until the cheese is bubbling and browning on top.
It might seem simple, but that browned, golden top really adds another layer of deliciousness to the potatoes that makes everyone want more.
Serve these up warm with a little added fresh thyme for color.
More Recipe Suggestions:
Cheesy Potato & Smoked Sausage Casserole
Original Recipe By; Half Baked Harvest
Lastly, if you make this Cheesy Scalloped Potatoes with Caramelized Onions, be sure to leave a comment and/or give this recipe a rating! Above all, I love to hear from you guys and always do my best to respond to each and every comment. And of course, if you do make this recipe, don’t forget to tag me on Instagram @northeast.nosh! Looking through the photos of recipes you all have made is my favorite!
Cheesy Scalloped Potatoes with Caramelized Onions
Equipment
Ingredients
- 3 tablespoons salted butter
- 1 yellow onion thinly sliced
- kosher salt and black pepper
- 1/4 cup dry white wine such as Pinot Grigio
- 1 clove garlic chopped
- 1 tablespoon chopped fresh thyme
- 2 cups heavy cream
- 1 cup whole milk
- 1 pinch cayenne
- 3/4 cup shredded Gruyere cheese
- 3/4 cup shredded cheddar cheese
- 6 russet or Yukon gold potatoes cut into 1/8-inch-thick slices
Instructions
- Preheat the oven to 350° F.
- Melt together the butter and onions in a large skillet over medium-high heat. Cook, stirring occasionally until softened, about 10 minutes. At this point, you’ll want to add the wine and continue to cook another 5 minutes until the onions are deeply caramelized.
- Add the garlic and thyme, then season with salt and pepper. Cook another 2 minutes, then remove from the heat.
- Butter a 9×13 inch casserole dish. In a large glass measuring cup, combine the cream, milk, a pinch of cayenne, salt, and pepper. Then add the Gruyere cheese. Pour 1/3 of the milk mix into the bottom of the baking dish. Layer in 1/3 of the potatoes, and 1/2 of the onions. Add another 1/3 milk mix, then 1/3 of the potatoes, and then the remaining onions. Add the remaining potatoes, then pour over the last of the remaining milk mix. Try to get the potatoes in an even layer.
- Cover and bake 1 hour 45 minutes to 2 hours. Remove the foil and top with cheddar cheese. Bake another 20 minutes, until the cheese is golden and melty. Serve the dish warm, topped with fresh thyme.
Notes:
- To make Ahead: prepare and bake through step 5 but stop cooking after 2 hours. Let chill, then cover, and keep in the fridge for up to 4 days. Before baking, bring the dish to room temperature, add the cheddar cheese, and bake another 20-30 minutes.
