Looking for new sides this holiday season? We got you covered with our delicious Creamy Scalloped Potatoes Au Gratin.
It has both russet and sweet potatoes, plus onion and yellow squash slices.
Yes, it looks so good, and the taste is delicious—Chef’s kiss!
When you need a good side dish for a holiday or dinner party, this creamy scalloped recipe will be a hit!
Creamy Scalloped Potatoes Au Gratin with Onion + Squash
Where do I begin with this recipe? When I first kitchen-tested this combination, it gave me Ratatouille vibes!
The alternating color scheme of the russets, sweet potatoes, onions, and yellow squash is appealing.
But it is the taste of this flavor bomb that will keep you coming back for more! And let us not talk about the creamy cheese sauce!
The cheese sauce is what makes this savory potato-and-vegetable combination go to infinity and beyond!
What You Will Need
Russet Potatoes and Garnet Sweet Potatoes. Working with good starchy potatoes is the foundation of this recipe. Russets are my preferred potato for this dish because of their starchiness and rich potato flavor, and they stand up well to high heat. They will also absorb butter and cheese sauce like no other. For the sweet potato choice, I love Garnet sweet potatoes! Yes, Garnet!
These sweet potatoes are noted for their ruby-colored skin and bright orange interior.
Garnets are less sweet than the more common Beauregard and Jewel sweet potato varieties, which makes them an ideal candidate for savory sweet potato dishes.
Garnets also contain more moisture, and when baked in this dish, the sweet potato will become creamy and delicate!
Onions and Yellow Squash. Aside from adding color contrast, onions to this dish add a savory element that complements the russet potato and balances out the slight sweetness of the sweet potato.
The yellow squash will become creamy, and its earthy rustic flavor works well with the other ingredients.
Butter and All-Purpose Flour. Making a roux is what gives the cheesy sauce in this recipe its body and makes everything all creamy and delectable.
Made with equal parts unsalted butter and all-purpose flour, cooked by whisking them together over medium-high heat.
Want to take it up a notch?
Replace the butter with bacon fat and let the sparks fly!
Heavy Whipping Cream. A lot of au gratin recipes use whole milk, not this one! For a creamier au gratin, I love using heavy whipping cream, or, in a pinch, half-and-half. But trust me, use the heavy whipping cream and you will not be disappointed. At all!
Seasonings. I’m using sea salt, freshly cracked black peppercorns, smoked paprika, and granulated onion or onion powder. This quartet of seasonings makes this potato-and-vegetable au gratin snap, crackle, and pop!
White Cheddar & Pecorino Cheese. OMG! The combination of white cheddar cheese and pecorino cheese makes each loving forkful dance on your taste buds like a breakdancer, and all you will want to do is shovel more into your mouth! Enough said!
Ingredients needed for this creamy scalloped au gratin recipe:
serving size: 6-8
- 4 medium russet potatoes, peeled and thinly sliced (1/8 inch)
- 2 large sweet potatoes, peeled and thinly sliced (1/8 inch)
- 1 large sweet onion, thinly sliced
- 1 large yellow squash, thinly sliced
- 1 tsp sea salt
- 1/2 tsp freshly ground black peppercorns (adjust to taste)
- 1/2 tsp smoked paprika (adjust to taste)
- 1/4 tsp onion powder (adjust to taste)
- 3 tsp all-purpose flour
- 3 tsp unsalted butter
- 2 1/4 cups half-n-half
- 2 cups freshly grated white cheddar
- 1/2 cup grated pecorino cheese or a good Parmigiano Reggiano, divided
- • 2-3 tbsp of chopped curly or flat-leaf parsley
Directions:
- Preheat oven to 350°F. Wash and peel the potatoes. Adjust a mandoline slicer to 1/8 and slice the russet potatoes, sweet potatoes, yellow squash, and onions.
- Alternate the slices in an 8″ x 10″ baking dish and set aside.
- Make the cream sauce. Place a large skillet over medium-low heat and add 3 tablespoons of unsalted butter.
- When the butter is melted, whisk in 3 tablespoons of all-purpose flour. Whisk the mixture until the roux becomes a light blond color. Whisk in the half and half.
- Add the grated white cheddar cheese a little at a time until it is fully incorporated.
- Whisk in the sea salt, freshly cracked black peppercorns, onion powder, and smoked paprika.
- Reduce the heat to low and cook until the mixture coats the back of a spoon.
- Pour the mixture over the sliced potatoes, squash, and onions.
- Scatter about half of the grated pecorino cheese over the potatoes, squash, and onions.
- Cover the dish tightly with foil, place it in the 350°F oven on the center rack, and bake for 45 minutes, until the potatoes are fork-tender.
- Remove the foil and continue baking for 15 more minutes to lightly brown the top and thicken.
- Remove the potato dish from the oven and evenly scatter the remaining grated pecorino cheese on top, finishing with chopped parsley.
- Serve.
Note: If your squash is very moist, lightly salt and pat dry before layering.
For a deeper golden crust, broil the top for about 1-2 minutes at the very end. You will need to stand and watch this so your dish doesn’t burn!
Slice thickness impacts the baking time. Check tenderness before removing from the oven.
Can I make this creamy potato au gratin recipe a day ahead?
Yes. Au gratin potatoes can be pre-made up to two days ahead.
To reheat, preheat the oven to 375°F, cover the dish with foil, and place it on the center rack.
Heat for 20-25 minutes. Remove from the oven and serve.
How long will creamy scalloped potatoes keep in the fridge?
Transfer the leftovers to an airtight dish and cover with a tight-fitting lid.
This dish will keep in the fridge for up to five days.
Can I freeze this au gratin scalloped potato recipe?
Absolutely. After baking, allow the dish to cool completely, then cover it with cling wrap and aluminum foil.
Store in the freezer for up to six months. To reheat, adjust the oven to 375°F, remove the cling wrap, and cover with the aluminum foil.
Place on the center rack of the oven and heat for thirty minutes, or until the dish is piping hot.
Now that you have the recipe, all you have to do is grab the ingredients and get in the kitchen.
And, as always, if you have any questions, drop us a line in the comments section down below! And if you make this recipe, let us know how it turned out!
Happy Holidays!
Find more holiday recipes to try:
Baked Butternut Squash Potatoes
Creamy Scalloped Au Gratin Potatoes with Squash + Onion
Ingredients
- 4 medium russet potatoes peeled and thinly sliced (1/8 inch)
- 2 large sweet potatoes peeled and thinly sliced (1/8 inch)
- 1 large sweet onion thinly sliced
- 1 large yellow squash thinly sliced
- 1 tsp sea salt
- 1/2 tsp freshly ground black peppercorns adjust to taste
- 1/2 tsp smoked paprika adjust to taste
- 1/4 tsp onion powder adjust to taste
- 3 tsp all-purpose flour
- 3 tsp unsalted butter
- 2 1/4 cups half-n-half
- 2 cups freshly grated white cheddar
- 1/2 cup grated pecorino cheese or a good Parmigiano Reggiano divided
- 2-3 tbsp of chopped curly or flat-leaf parsley
Instructions
- Preheat oven to 350°F. Wash and peel the potatoes. Adjust a mandoline slicer to 1/8 and slice the russet potatoes, sweet potatoes, yellow squash, and onions.
- Alternate the slices in an 8" x 10" baking dish and set aside.
- Make the cream sauce. Place a large skillet over medium-low heat and add 3 tablespoons of unsalted butter.
- When the butter is melted, whisk in 3 tablespoons of all-purpose flour. Whisk the mixture until the roux becomes a light blond color. Whisk in the half and half.
- Add the grated white cheddar cheese a little at a time until it is fully incorporated.
- Whisk in the sea salt, freshly cracked black peppercorns, onion powder, and smoked paprika.
- Reduce the heat to low and cook until the mixture coats the back of a spoon.
- Pour the mixture over the sliced potatoes, squash, and onions.
- Scatter about half of the grated pecorino cheese over the potatoes, squash, and onions.
- Cover the dish tightly with foil and Place the dish in the 350°F oven on the center rack and bake for 45 minutes, until the potatoes are fork-tender.
- Remove the foil and continue baking for another 15 minutes to lightly brown and thicken the top.
- Remove the potato dish from the oven and evenly scatter the remaining grated pecorino cheese on top, finishing with chopped parsley.
- Serve.
- Note: If your squash is very moist, lightly salt and pat dry before layering.
- For a deeper golden crust, broil the top for about 1-2 minutes at the very end. You will need to stand and watch this so your dish doesn’t burn!
- Slice thickness impacts the baking time. Check tenderness before removing from the oven.
Amber Johnson says
This looks absolutely amazing!! Can’t wait to try it!