Ingredients
Method
1. Prep the Veggies
Peel the potatoes and slice them into thin, even rounds—about ⅛-inch thick works best. Uniform slices help everything cook at the same pace. Thinly slice the onion so it melts right into the layers while baking.
2. Build the Creamy Sauce
Place a saucepan over medium heat and melt the butter. Whisk in the flour and cook for 1–2 minutes until smooth and lightly golden. Slowly pour in the milk while whisking to avoid lumps. Keep stirring until the sauce thickens to a pourable, creamy texture. Season with salt and pepper and set aside.
3. Assemble the Layers
Grease a baking dish well. Arrange a layer of potatoes on the bottom, scatter a few onion slices on top, then spoon over some sauce. Add a sprinkle of cheese if using. Repeat the layers until everything is used, finishing with sauce and cheese on top.
4. Bake Until Golden
Cover the dish with foil and bake at 350°F (175°C) for 45 minutes. Remove the foil and continue baking for another 15 minutes, or until the top is bubbly and lightly browned.
5. Rest & Serve
Let the dish sit for about 5 minutes before serving. Finish with fresh herbs for a pop of color and flavor.
Notes
Helpful Notes
- Slice evenly: Thin, consistent potato slices cook more evenly and absorb the sauce better.
- Switch up the cheese: Try Gruyère, Swiss, or Parmesan for a different flavor profile.
- Storing leftovers: Keep refrigerated in an airtight container for up to 3 days.
Why This Recipe Works
- Beginner-friendly: Simple ingredients and clear steps make this easy to pull off.
- Goes with everything: From roast chicken to steak, this side fits right in.
- Flexible flavors: Adjust cheese, herbs, or seasonings to suit your taste.
- Always a hit: Creamy layers + tender potatoes = universal approval.
- Make-ahead friendly: Assemble in advance and bake when ready to serve.
Expert Tips
- Use a mandoline: It’s the easiest way to get uniform slices fast.
- Don’t rush the sauce: Let it thicken slowly for the smoothest texture.
- Choose the right dish: A 9×13-inch pan gives the layers room to cook evenly.
- Season smart: Taste the sauce before layering—bland sauce = bland potatoes.
FAQs
Can I assemble this ahead of time?Absolutely. Assemble the dish, cover tightly, and refrigerate for up to 24 hours. Add a few extra minutes to the baking time if starting cold. Why did my scalloped potatoes turn watery?
This usually happens if the sauce wasn’t thick enough or if low-starch potatoes were used. Russets or Yukon Golds are your best bet. Can scalloped potatoes be frozen?
Yes, but expect some texture changes. Cool completely, freeze in an airtight container, and reheat in the oven for best results. Is peeling the potatoes required?
Not at all. Leaving the skins on adds texture and fiber, though the dish may be slightly less creamy. How do I make it gluten-free?
Swap the flour for gluten-free flour or cornstarch when making the sauce, whisking well to prevent clumps.