Cheesy Scalloped Potatoes
Thin Yukon Gold potatoes cook in layers of creamy cheddar sauce in a slow cooker, then get a melted cheddar-and-Parmesan topping. The finished potatoes are tender and saucy enough to scoop, rather than cut into squares. An oval cooker gives the slices room to form even layers while leaving the oven free.
Slice the potatoes uniformly, cook on HIGH, and begin checking the center at four hours. Once the potatoes are fork-tender, an uncovered rest helps the sauce cling to each spoonful.
Ingredients for Cheesy Scalloped Potatoes

- 3 pounds Yukon Gold potatoes (about 1,350g), peeled or scrubbed
- 3 tablespoons unsalted butter (about 45g), divided
- 1 medium yellow onion (about 150g)
- 1 1/2 cups whole milk (360g)
- 3/4 cup sour cream (180g)
- 2 1/2 cups freshly shredded sharp cheddar (about 285g), divided
- 1/2 cup finely grated Parmesan (about 50g), divided
- 1 1/2 teaspoons kosher salt
- 1/2 teaspoon black pepper
- 1/2 teaspoon garlic powder
- 2 tablespoons chopped chives or flat-leaf parsley
Freshly shred the cheeses if possible; block cheese generally melts more smoothly than pre-shredded cheese. A mandoline makes the potato slices easier to keep at a consistent thickness. Use its guard or a cut-resistant glove.
How to Make Cheesy Scalloped Potatoes in the Slow Cooker

- Prepare the cooker and vegetables: Coat the insert of a 5- to 6-quart oval slow cooker with 1 tablespoon butter. Slice the potatoes into uniform 1/8-inch rounds and the onion very thinly. Thick potato slices may still be firm when the thinner ones are done.
- Mix the sauce: Melt the remaining 2 tablespoons butter. In a large bowl, whisk it with the milk, sour cream, salt, pepper, and garlic powder. Stir in 1 1/2 cups cheddar and 1/4 cup Parmesan; reserve the remaining cheeses for the top. The mixture should be pourable, with visible cheese shreds.
- Build the layers: Arrange one-third of the potatoes in broad, overlapping layers in the insert. Add one-third of the onion and spoon over one-third of the sauce. Repeat twice, ending with sauce. Gently press the top slices into the liquid without packing the layers tightly. Keep the cooker no more than about three-quarters full.
- Cook until tender: Cover and cook on HIGH for 4 to 5 hours. Begin checking at 4 hours with a fork or thin knife, testing the center as well as the outer layers. If the potatoes resist, cover and check again every 15 to 20 minutes. Stop when the slices are easily pierced but still distinguishable and the sauce bubbles at the edges. Do not stir during cooking.
- Melt the topping: Scatter the reserved cheddar and Parmesan over the tender potatoes. Cover and cook on HIGH for 10 to 15 minutes more, until the cheese is melted and glossy.
- Rest and serve: Turn off the cooker and remove the lid. Let the potatoes stand uncovered for 10 to 15 minutes so the sauce thickens. Scatter the chives or parsley over the top and serve saucy spoonfuls from the insert.
What to Expect From the Slow-Cooker Finish
Use fork tenderness rather than the clock alone: the center can take longer than the layers near the hot outer edge, and slow cookers vary. Cooking on HIGH and stopping as soon as the potatoes are tender helps the slices hold their shape.
The topping will be melted and lightly mottled, not crisp like an oven-baked crust. For optional browning, transfer the cooked potatoes to a broiler-safe baking dish and broil briefly. Never put a slow-cooker insert under the broiler unless its manufacturer explicitly says it is broiler-safe.
Serving and Storing Leftovers
Serve alongside roasted chicken, grilled steak, or a green vegetable. For a sweet-tart side at a larger meal, add cranberry Jello salad with pineapple and orange.
Cool leftovers promptly, transfer them to a shallow airtight container, and refrigerate for 2 to 3 days. Reheat covered at 350°F (175°C) for about 30 minutes, or until hot throughout. Add a small splash of milk or cream if the potatoes look dry.
Nutrition
Approximate nutrition per serving, based on 8 side-dish servings: 420 calories, 17g protein, 24g fat, and 35g carbohydrates. Per 100g of finished potatoes: approximately 150 calories, 6g protein, 9g fat, and 13g carbohydrates. Values vary with ingredient brands, portion size, and moisture lost during cooking.
Equipment
- 5- to 6-quart oval slow cooker
- mandoline or sharp knife
- large bowl
- whisk
- measuring cups and spoons
Ingredients
For the Potatoes and Sauce
- 3 pounds Yukon Gold potatoes (about 1,350g), peeled or scrubbed
- 3 tablespoons unsalted butter (about 45g), divided
- 1 medium yellow onion (about 150g), thinly sliced
- 1 1/2 cups whole milk (360g)
- 3/4 cup sour cream (180g)
- 2 1/2 cups freshly shredded sharp cheddar (about 285g), divided
- 1/2 cup finely grated Parmesan (about 50g), divided
- 1 1/2 teaspoons kosher salt
- 1/2 teaspoon black pepper
- 1/2 teaspoon garlic powder
For Garnish
- 2 tablespoons chopped chives or flat-leaf parsley
Instructions
- Coat the insert of a 5- to 6-quart oval slow cooker with 1 tablespoon butter.
- Slice the potatoes into uniform 1/8-inch rounds and slice the onion very thinly.
- Melt the remaining 2 tablespoons butter.
- Whisk the melted butter, milk, sour cream, salt, pepper, and garlic powder in a large bowl.
- Stir 1 1/2 cups cheddar and 1/4 cup Parmesan into the sauce mixture, reserving the remaining cheeses for topping.
- Arrange one-third of the potatoes in overlapping layers in the slow cooker. Top with one-third of the onion and one-third of the sauce.
- Repeat the layers twice, ending with sauce. Gently press the top potato slices into the liquid without packing them tightly.
- Cover and cook on HIGH for 4 to 5 hours. Start checking the center at 4 hours and continue checking every 15 to 20 minutes until the potatoes are easily pierced with a fork or thin knife.
- Scatter the reserved cheddar and Parmesan over the potatoes. Cover and cook on HIGH for 10 to 15 minutes, until the cheese is melted and glossy.
- Turn off the slow cooker, remove the lid, and let the potatoes rest uncovered for 10 to 15 minutes.
- Garnish with chives or parsley and serve.
Tips
- Use a mandoline or sharp knife to keep potato slices an even 1/8-inch thickness.
- Freshly shredded block cheese melts more smoothly than pre-shredded cheese.
- Keep the slow cooker no more than about three-quarters full.
- Test potatoes in the center, since the middle may cook more slowly than the outer layers.
- Do not stir the potatoes while they cook.
- Use fork tenderness rather than cooking time alone to judge doneness.
Variations
- Broiled Cheese Topping: For a browned topping, transfer the cooked potatoes to a broiler-safe baking dish and broil briefly. Do not broil the slow-cooker insert unless the manufacturer confirms it is broiler-safe.
