Name: Potato Leek Gratin
Prep time: 25 min
Cook time: 1 h
Total time: 1 h 25 min
Yield: 10
Ingredients: Cooking spray; 3 pounds russet potatoes; 1 cup half and half; 1 cup chicken broth; 1/4 cup horseradish; 2 teaspoons Dijon mustard; 3/4 cup Gruyere cheese; 3/4 cup Fontina cheese; 3 slices of bacon, cooked and crumbled; 1 leek, including part of the green section, sliced into skinny rounds, sauteed; salt and pepper

Jump to Recipe

Potato Leek Gratin is an easy side dish and family favorite! It’s filling, yummy, and perfect!

This is the ultimate comfort food! Layers of tender potatoes, creamy sauce, and melted cheese.

How can you resist? I know I can’t!

My family absolutely adores this dish!

This leek and potato gratin is an easy recipe you’ll come back to over and over!

It’s perfect for any holiday meal too! It goes with everything!

The cheeses give it a yummy and nutty flavor that is SO good!

It makes a bunch too so it’s perfect for serving a crowd.

This bacon potato bake will have you coming back for seconds!

What Ingredients Are in Potato Leek Gratin?

This potato gratin recipe has got to be my favorite way to use these cheeses!

Here’s what you’ll need to get your perfect Christmas dinner (or any other dinner) started:

Russet Potatoes: Peeled potatoes thinly sliced for tender layers.
Light Cream: Love that cream!
Chicken Broth: Makes the cream sauce awesome.
Horseradish: Gives a subtle kick (strained out later).
Dijon Mustard: Nice and tangy!
Gruyere and Fontina Cheese: Creates a creamy and nutty cheese blend.
Bacon: Cooked and crumbled.
Leek: Sauteed and added for a mild onion flavor.
Salt and Pepper: A little seasoning!

Pro Tips:

Use a food processor to slice the potatoes evenly and thinly.
You could also use Yukon gold potatoes but they’ll be much softer.
Give the potatoes a good rinse before using them.

How to Make Potato Leek Gratin?

This potato casserole is gonna have everyone lining up to be your recipe tester!

The whole recipe card is below but here’s what you need to know:

In a large bowl, whisk together light cream, chicken broth, Dijon mustard, and horseradish.
Place slice potatoes bottom of the pan, sprinkle with salt and pepper, add cheese, and cream mixture.
Repeat twice more. Try to get even layers.
Bake until golden brown on top of the gratin and tender.
Put crumbled bacon and sauteed leeks on top of the dish.

Pro Tip: Let the gratin cool for 10 minutes before serving to set the layers.

Can You Prepare Potato Leek Gratin Ahead of Time?

Yes, you can prepare this side dish recipe ahead of time!

Assemble the gratin but do not bake it.

Cover tightly with plastic wrap or aluminum foil.

Then refrigerate for up to 24 hours.

When you’re ready to bake, let it come to room temperature before placing it in the oven.

This makes it a perfect side dish for busy holiday dinners or large gatherings!

Can I Use Ham Instead of Bacon in Potato Leek Gratin?

Absolutely! Ham is a delicious alternative to bacon.

And it’s a great way to use up leftover holiday ham if you have it!

Simply dice the ham and layer it with the potatoes and cheese.

You could also add it over the final layer of potatoes like the bacon if you want.

It adds a wonderful flavor and pairs perfectly with the creamy sauce and Gruyère cheese.

How to Store Potato Leek Gratin?

Store any leftovers of the finished dish in an airtight container in the fridge.

It will last for up to 5 days.

That is, if you can keep from eating it that long! Yum!

To reheat, place portions in a baking dish.

Then warm in a 350°F oven until heated through.

Remember it just needs to be warm.

Don’t cook it all over again.

Cover with foil to prevent the top from browning too much.

You could also reheat it in the microwave but I like the oven texture better.

Can You Freeze Potato Leek Gratin?

Yes, you can freeze this easy holiday dinner!

Allow the dish to cool completely.

Then wrap tightly with aluminum foil and plastic wrap.

Freeze for up to 3 months.

To reheat, thaw in the refrigerator overnight and then reheat.

This way you’ve got a good time just waiting in a casserole dish in your freezer!

So easy! Plus, you can also freeze it before baking.

Then just add extra time to the baking time and bake straight from the freezer.

If you put it in one of those give away baking dishes then you can take this to a sick neighbor too!

It’s a great one to have in the freezer!

What to Serve with Potato Leek Gratin?

This decadent side dish goes really well with roasted meats.

Try it with roast chicken, beef tenderloin, or a holiday ham.

It also goes well with vegetable dishes like green beans or roasted Brussels sprouts.

Here are some ideas you should definitely try:

How Long Does Potato Leek Gratin Last?

This au gratin potato slices dish lasts for about 5 days in the refrigerator.

Keep it stored in an airtight container so it’ll stay fresh and yummy.

Reheat portions in the oven for best results.

Remember to always let it cool completely.

If it is still hot when you put it in your container, it’ll sweat.

Additional Leek Recipes You’ll Love…

Potato Leek Gratin is an easy holiday or weeknight dinner side dish!

It’s delicious, filling, and hearty!

It’ll be a family favorite in no time! Enjoy!

Potato Leek Gratin

Yield: 10 Servings

Prep Time: 25 minutes

Cook Time: 1 hour

Total Time: 1 hour 25 minutes

This Potato Leek Gratin is the ultimate comfort food with layers of tender potatoes, creamy sauce, and melted Fontina and Gruyere cheese.

Ingredients

Instructions

Preheat your oven to 400 degrees.
Prepare a 9" x 13" baking dish by spraying with cooking spray.
Combine half and half, chicken broth, Dijon mustard and horseradish. Whisk to combine; set aside.
Grate cheeses; set aside.
Peel potatoes and slice with food processor or mandolin into thin slices.
Strain your light cream / chicken broth mixture through wire mesh strainer into another bowl. The horseradish will be left behind in the strainer. You will not need it for the rest of the recipe.
Place about 1/3 of your potatoes in your prepared baking dish. Sprinkle with salt and pepper. Top with 1/3 of the cheese mixture, and then pour approximately 1/3 of the half and half / chicken broth mixture over the top of the potatoes.
Repeat layers two more times.
Bake for approximately 1 hour, until potatoes are fork tender. The top should be golden brown and little crusty.
While potatoes are baking, cook 3 slices of bacon, drain and crumble. Reserve about 1 tablespoon of bacon grease to cook leek rounds. Once softened, drain on paper towels.
When potatoes have about 5 minutes left to cook, top with bacon and leeks.
Cool for 10 minutes or so before serving. If you don't plan to serve right away, cover with aluminum foil until ready to serve.

Notes

When you slice your potatoes, you may find that they turn pink.

To avoid making your dish with pink potatoes, simply place the potato slices in a bowl of cold water and drain them when you are ready to use them.

The water will turn pink, and the potatoes will return to normal color.

Nutrition Information:

Yield: 10 Serving Size: 1
Amount Per Serving: Calories: 259Total Fat: 10gSaturated Fat: 6gTrans Fat: 0gUnsaturated Fat: 4gCholesterol: 33mgSodium: 404mgCarbohydrates: 32gFiber: 4gSugar: 4gProtein: 11g

Originally Posted: July 17, 2016

Photos & Text Updated: October 6, 2024

Lisa @ Fun Money Mom

Saturday 30th of July 2016

This sounds so delicious and I'll definitely have to try making it sometime soon! Thanks for sharing with us at Share The Wealth Sunday. I hope we see you again tonight!

DearCreatives (@DearCreatives)

Friday 29th of July 2016

Oh, fall foods. YUM! Thanks for sharing at the Inspiration Spotlight party. Shared.

Cindy

potatoes, cheese & bacon... that's a winning combination! Although I think I'll just use green onions instead of leeks.

leighdstr

Wednesday 27th of July 2016

Michelle, this potato dish is to die for! My family thanks you so!

pattyanderson54p

My husband would love this dish. I am especially grateful for the added tips!