Slow Cooker Cheesy Scalloped Potatoes Recipe

I’m sharing my favorite Thanksgiving shortcut with Slow Cooker Scalloped Potatoes that frees up oven space and produces a creamy, cheesy potato side from the crockpot.

I never thought a Thanksgiving side could steal the show, but these Slow Cooker Scalloped Potatoes almost did. I wanted something to free up oven space so I could focus on the bird, and this felt like cheating in the best way.

Layered Yukon Gold potatoes with melted sharp cheddar cheese give it that creamy, slightly sharp bite that makes people go quiet for a second, then reach for more. It feels fancy but it really isn’t, so it’s my go to Easy Crockpot Dinners pick when I need to impress without sweating it.

I swear every year someone begs for the recipe.

Ingredients

• Potatoes: starchy, good source of carbs and potassium, makes dish creamy and filling.
• Sharp cheddar cheese: adds savory tang, lots of protein and calcium, brings melty richness.
• Whole milk and cream: boost fat and creaminess, help thick sauce and mouthfeel.
• Butter and flour roux: creates a silky base, adds fat and slight savory notes.
• Onion: brings natural sweetness and depth, adds subtle savory and caramelized flavors.
• Garlic: gives sharp aromatic bite, small amount goes a long ways.
• Thyme and Parmesan: herb adds earthiness, Parmesan adds saltiness and umami finish.

Ingredient Quantities

• 3 lb Yukon Gold or russet potatoes, thinly sliced (about 6 medium)
• 1 medium yellow onion, thinly sliced
• 2 garlic cloves, minced
• 3 tbsp unsalted butter
• 3 tbsp all purpose flour
• 2 cups whole milk
• 1 cup heavy cream
• 2 cups sharp cheddar cheese, shredded (about 8 oz)
• 1/2 cup grated Parmesan cheese
• 1 1/2 tsp kosher salt
• 1/2 tsp black pepper
• 1/2 tsp dry mustard
• 1/2 tsp dried thyme (or 1 tsp fresh thyme leaves)
• 2 tbsp chopped fresh chives or parsley, for garnish (optional)

How to Make this

1. Wash and peel the potatoes if you like, then slice them thin about 1/8 inch (a mandoline helps), thinly slice the onion and mince the garlic.

2. Melt the 3 tbsp butter in a medium saucepan over medium heat, stir in the 3 tbsp flour and cook 1 minute until it smells nutty, stirring so it doesn’t brown.

3. Slowly whisk in the 2 cups whole milk and 1 cup heavy cream so no lumps form, bring to a gentle simmer and cook until the sauce thickens about 3 to 4 minutes.

4. Stir the minced garlic, 1 1/2 tsp kosher salt, 1/2 tsp black pepper, 1/2 tsp dry mustard and 1/2 tsp dried thyme into the sauce, then melt in 1 1/2 cups shredded sharp cheddar and the 1/2 cup grated Parmesan until smooth; reserve about 1/2 cup cheddar for topping.

5. Lightly grease the slow cooker with butter or nonstick spray. Layer half the sliced potatoes, then half the onion, sprinkle a tiny pinch of salt and pepper, then repeat with the rest of the potatoes and onion.

6. Pour the cheesy sauce evenly over the potato layers, press down gently so the sauce seeps in, cover and cook on low for 4 to 5 hours or on high for 2 1/2 to 3 hours until potatoes are tender when pierced with a knife.

7. If the sauce is too thin at the end, mix 1 teaspoon cornstarch or 1 tablespoon flour with a little cold milk to make a slurry and stir into the crock, cook uncovered 15 to 20 minutes to thicken; don’t worry, you can fix a runny sauce this way.

8. About 10 to 15 minutes before serving sprinkle the reserved cheddar over the top, recover and let it melt; for a browned top, transfer to a baking sheet and broil in a hot oven for 2 to 4 minutes but watch it closely.

9. Let the scalloped potatoes rest 10 minutes to set, then garnish with 2 tbsp chopped fresh chives or parsley and serve warm.

Equipment Needed

1. Mandoline or very sharp chef’s knife for thin 1/8 inch potato slices, mandoline makes it quick but be careful
2. Vegetable peeler for peeling potatoes, or skip if you like the skins
3. Large cutting board to slice potatoes and onions on
4. Medium saucepan for making the roux and cheese sauce
5. Whisk to blend the milk and cream and keep sauce lump free
6. Measuring cups and measuring spoons for milk, cream, flour and seasonings
7. Slow cooker or crockpot big enough for about 3 pounds of potatoes
8. Box grater or microplane to shred cheddar and grate Parmesan
9. Rubber spatula or wooden spoon, plus a small bowl for the cornstarch slurry and an ovenproof baking sheet if you want to broil the top

FAQ

Slow Cooker Cheesy Scalloped Potatoes Recipe Substitutions and Variations

• Potatoes (Yukon Gold or russet): swap for red potatoes if you want firmer, less starchy slices; slice the same thickness, they hold up better. Or use sweet potatoes for a sweeter, colorful twist, but cut salt a bit and check doneness earlier since they can cook faster.
• Whole milk + heavy cream: replace the 2 cups milk + 1 cup cream with 3 cups half and half for similar creaminess. For a dairy free option use full fat canned coconut milk, it’ll add a hint of coconut so taste and adjust seasonings.
• Sharp cheddar cheese: use Gruyere or Fontina for a nuttier, super melty result; keep the same cup amount. If you want milder cheese try Monterey Jack or Colby.
• All purpose flour (thickener): use cornstarch instead, about 1 1/2 tbsp cornstarch mixed with cold water as a slurry and stir in near the end until thick. You can also use equal parts gluten free flour or tapioca starch if needed.

Pro Tips

– Slice even, about 1/8 inch if you can. A mandoline makes this easy, but if you use a knife try to keep them consistent or some pieces will be done way before others and you’ll get mushy bits mixed with undercooked ones.

– Taste the finished bechamel before you pour it over the potatoes. Cheeses and salts vary alot so add salt slowly, you can always add more but you cant take it out. If it tastes a little flat, an extra pinch of dry mustard or a splash more Parmesan fixes it.

– Grate your own cheddar, dont use pre shredded if you want a silky sauce. The pre shredded stuff has anti caking powders so it never melts as smooth, and reserve some cheese for the top so it browns nicely at the end.

– Prevent a soggy bottom by layering a thin ring of onions or a light buttered foil under the potatoes, and cook on low if you can. Check for tenderness early, and let the dish rest 10 minutes after cooking so the sauce firms up, otherwise it will be runny when you cut it.