Crock Pot Au Gratin Potatoes – A Classic Holiday Side Dish Recipe

This Crock Pot Au Gratin Potatoes recipe is one of our most popular recipes around the holidays. Thinly sliced potatoes that are layered in a homemade cheese sauce and cooked until nice and tender.

Not only are they delicious, they are easy to make! And best of all, they are cooked in a slow cooker so that you can save room in your oven for the main dish.

Not to mention that because you are making them in your crock pot, they become an easy to transport recipe. Especially if you have a slow cooker with a lockable lid, like my 6 quart Programmable Crock Pot.

Simply lock the lid in place and there are no worries of the lid slipping off during the transport and making a mess in your car.

Crock Pot Au Gratin Potatoes Recipe

*Complete recipe instructions including specific measurements, cook temperatures and times are located in a printable recipe card at the bottom of this article. However, be sure to keep reading for helpful tips and tricks when making this recipe.

INGREDIENTS

1. Yukon Gold potatoes

Although you could use standard Russet potatoes, Yukon gold potatoes will provide the most flavor in this recipe. Another advantage of using Yukon gold potatoes is that you don’t have to peel the potatoes if you don’t want to. The thin skin will become nice and tender during the cooking process, unlike the peel of Russet potatoes.

2. Small onion

You can use a yellow, white or sweet onion in this dish. The key here is to dice the onion finely so that you get the subtle flavor of the onion, but not a strong onion taste.

3. Unsalted butter

As always, I recommend using unsalted butter. You can always add more salt later if needed.

4. All-purpose flour

The flour is used to thicken the cheese sauce. However, to make this recipe gluten-free use a gluten-free all-purpose flour instead. The sauce will still thicken and those that can’t have gluten will still be able to enjoy the taste of your Crock Pot Au Gratin Potatoes!

5. Whole milk

Whole milk is preferred because it is thicker than 2% or skim milk. You could also use heavy cream or half and half as a substitute.

6. Garlic powder

Although I prefer to use fresh garlic in most of my recipes, it is much easier to use garlic powder in this recipe. In order to flavor the potatoes, you would have to use an entire bulb of fresh garlic, if not more. So instead, we will stick to garlic powder to keep things easier.

7. Salt & Ground Black Pepper

In the recipe card below, I have listed the specific amount of salt and pepper that I use in this recipe. However, feel free to adjust the amounts based on your taste preference.

8. Shredded Cheese

It is best to use a combination of cheese varieties to gain the most flavor. I prefer a blend of Monterey Jack and Sharp Cheddar cheese.

However, feel free to substitute Gruyere, Gouda, or any other type of cheese that you prefer.

The most important thing to know about the cheese is that you should not use pre-packaged shredded cheese. That is because it is coated with an anti-caking agent when it is packaged. Therefore, when melted, it becomes stringy.

Instead, use a food processor or cheese grater and shred your own cheese. It only takes a few minutes and it is well worth doing the extra dish during clean up!

How To Make Crock Pot Au Gratin Potatoes

The first step is to decide whether or not you want to peel your potatoes. As mentioned above, if you use Yukon gold potatoes, the skins can be left on if desired.

However, I most often peel the potatoes before slicing them, although this is strictly a personal preference.

Once the potatoes are washed (and peeled if doing so) cut them in 1/8″ thick slices. This is where a mandoline slicer comes in handy if you have one.

When I use my mandoline slicer, I can cut all my potatoes in minutes as compared to slicing them by hand with a sharp knife. Just be sure to use the hand guard that comes with it!

Once your potatoes are sliced, set them aside and prepare the slow cooker by generously spraying non-stick cooking spray in the liner. Then set the crock pot aside and prepare the cheese sauce.

Cheese Sauce

Place a medium saucepan over medium-low heat and add the butter. Once the butter melts whisk in the flour until the dry flour is no longer visible. 

Then add the milk, garlic powder, salt and pepper, and whisk to combine. Continue to cook just until it starts to thicken, whisking frequently.

Once the sauce coats the back of a spoon, remove the pan from the heat. Then stir in the shredded cheese until melted. Set the pan aside and begin to lay the Au Gratin Potatoes in the crock pot.

Start by adding 1/3 of the sliced potatoes in the bottom of the slow cooker.  Then sprinkle 1/3 of the chopped onion on top of the potatoes.

Complete the first layer by pouring 1/3 of the cheese sauce over the potatoes and onions.  Repeat these layers 2 more times, ending with the cheese sauce on top.

Cover and cook on high for 3-4 hours or low for 4-6 hours or until potatoes are tender. *Slow Cooker cook times will vary based on the brand that you have and the times may need adjusted accordingly.

Once the potatoes can easily be pierced with a fork, turn off the heat. Then let the potatoes sit for 20 minutes before serving to allow time for the sauce to thicken.

If you want the cheese sauce to brown on top, use a culinary torch to heat the top. Or transfer the potatoes to a broiler safe dish, add a little more cheese on top and broil until the cheese turns light golden brown in color.

When serving, garnish with chopped fresh parsley if desired.

Enjoy!

Mary and Jim

Jim and Mary Competti have been writing gardening, DIY and recipe articles and books for over 15 years from their 46 acre Ohio farm. The two are frequent speakers on all things gardening and love to travel in their spare time.

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