Crockpot Potato Gratin is the ultimate side dish that’s creamy, cheesy, and ridiculously easy to make. This slow cooker recipe is my go-to for holidays, potlucks, or even busy weeknights when I just don’t have the time (or energy) to fuss with a traditional gratin. It’s classic comfort food with none of the hassle.

I discovered this shortcut when I realized how much work goes into traditional potato gratin—slicing, par-cooking, layering, then baking for almost an hour. My favorite kitchen buddy, the slow cooker, does all of that for me. You’ll end up with tender Yukon gold potatoes smothered in a velvety cheese sauce, all while you handle the rest of life. Trust me, this shortcut is a total game-changer!

Why This Crockpot Potato Gratin Is a Game-Changer

No pre-cooking needed: Forget boiling or baking the potatoes first. Just layer them up and let the slow cooker do all the heavy lifting.
Hands-off cooking: Once you set it, you can walk away for up to 4 hours while it works its magic.
Perfect textures: The slow cooker keeps the potatoes tender and creamy, not mushy, as they soak up all that cheesy goodness.
Saves oven space: Ideal for holidays when your oven is packed with the main course and other sides.
Make-ahead friendly: Cook it in advance and reheat—it’s just as delicious the next day!

Equipment You’ll Need for This Crockpot Potato Gratin

To make this slow cooker potato casserole, you’ll need just a few essentials:

Slow cooker: I recommend at least a 6-quart size for this recipe to fit all the layers comfortably. Models with a High setting make quick work of this dish.
Mandoline or sharp knife: For slicing the Yukon gold potatoes into uniform 1/8-inch thick pieces. This ensures even cooking.
Disposable liner (optional): While not essential, it makes cleanup a breeze.

Pro tip: If your crockpot tends to run hot, check the potatoes around the 3-hour mark to avoid overcooking.

Simple Ingredients for Crockpot Potato Gratin

This is truly an easy cheesy potato gratin, with simple ingredients that pack a ton of flavor. Here’s what you’ll need:

Yukon gold potatoes: Their creamy texture makes them the perfect choice. You can peel or leave the skin on for added texture (and less peeling!).
Cheddar and Parmesan cheese: Cheddar adds that classic melty richness, while Parmesan brings a savory depth.
Sour cream chive dip: This shortcut ingredient adds tangy creaminess and a subtle herby twist—no need to chop fresh chives!
Milk and butter: For creating a luscious sauce base that binds everything together.

If you’re missing an ingredient, don’t worry—this recipe is forgiving. Swap sour cream dip for plain sour cream or cream cheese, or use any melty cheese you have on hand.

Crockpot Potato Gratin Recipe Details

Servings: 8
Prep Time: 30 minutes
Cook Time: 3-4 hours
Total Time: 3 hours 30 minutes

Crockpot Potato Gratin Ingredients

2 pounds Yukon gold potatoes (peeled if desired, sliced 1/8-inch thick)
1 1/2 cups milk
1/2 cup sour cream chive dip
3 tablespoons butter, cut into 3 pieces
3 tablespoons all-purpose flour
3/4 teaspoon salt, divided
1 1/2 cups shredded Cheddar cheese
1/4 cup freshly grated Parmesan cheese
1/2 teaspoon garlic powder
1/4 teaspoon freshly ground black pepper
1/2 cup chopped onion, divided
Chopped fresh chives (optional, for garnish)

How to Make Crockpot Potato Gratin

Start by gathering all of your ingredients. Prep the potatoes by slicing them into uniform 1/8-inch thick rounds (I recommend using a mandoline for consistency).
Line your 6-quart slow cooker with either a disposable liner or generously coat it with nonstick spray to prevent sticking.
In a small saucepan, melt butter over medium heat. Whisk in flour and 1/2 teaspoon salt. Cook for about 1 minute, stirring constantly, to form a roux.
Gently whisk the milk and sour cream dip into the roux. Bring it to a boil over medium-high heat, whisking constantly, then reduce to medium and cook until thickened (about 1 minute).
Remove from heat and whisk in the shredded Cheddar cheese until melted into a smooth, velvety sauce.
In a small bowl, mix together Parmesan cheese, garlic powder, the remaining 1/4 teaspoon salt, and black pepper.
Layer half the potato slices in the bottom of your slow cooker. Sprinkle with half of the Parmesan mixture, half the chopped onion, and half the cheese sauce. Repeat with the remaining potatoes and toppings.
Cover the slow cooker opening with paper towels to absorb excess moisture and secure the lid. Cook on High for 3-4 hours, or until the potatoes are fork-tender. Replace the paper towels halfway through cooking if they become saturated.
Once cooked, garnish with chopped chives and serve hot!

Jake’s Tips for the Best Crockpot Potato Gratin

Use a mandoline: Evenly sliced potatoes cook more consistently—and faster!
Don’t skip the paper towels: They make a huge difference, keeping the gratin’s texture creamy without being watery.
Make ahead: You can prepare the layers the night before, refrigerate, and cook the next day.
Freezer-friendly: Freeze leftovers in airtight containers. Reheat in the microwave or oven for a quick side on busy nights.

Easy Crockpot Potato Gratin Variations

Bacon-loaded: Add cooked, crumbled bacon between the potato layers for a smoky, savory twist.
Green goddess: Toss in spinach, kale, or frozen broccoli for a veggie-packed casserole.
Southwestern: Swap Cheddar for Pepper Jack and mix in diced green chilies for a spicy kick.
Ham and cheese: Layer sliced ham along with the potatoes for a hearty, one-pot meal.

Crockpot Potato Gratin FAQs

Can I use other types of potatoes?

Absolutely! While Yukon gold potatoes gratin has a creamy texture, russets or red potatoes work well too. Just aim for uniform slices.

Why do I need paper towels under the lid?

Paper towels help absorb condensation, preventing the gratin from becoming too watery. This step makes a big difference in the final texture.

Can I double this recipe?

If your slow cooker is large enough (8 quarts or more), you can double the recipe. Just expect slightly longer cooking times.

How do I reheat leftovers?

Reheat in the microwave for 1-2 minutes per serving, or bake at 350°F for about 15 minutes until warmed through.

Can I use pre-shredded cheese?

You can, but freshly shredded cheese melts smoother without the added anti-clumping agents found in pre-shredded varieties.

This Crockpot Potato Gratin is a shining example of how your slow cooker can simplify your cooking life while delivering incredible flavor. Give it a try—I promise, it’ll become a permanent fixture in your recipe rotation. So, what’s your favorite kitchen hack or time-saving recipe? Let me know in the comments below!