Leek and Onion Scalloped Potatoes Recipe

Okay, my food-loving friends, gather ’round! I have a confession to make. I am completely, utterly obsessed with this Leek and Onion Scalloped Potatoes recipe. It’s the dish I daydream about. If you love creamy, vegetable-forward dishes, you must try our velvety French potato and leek potage.

You know, the one you bring to the table and everyone just goes silent? That’s this. It’s creamy, it’s cozy, and it has the most incredible mild onion flavor that just wraps around every single potato slice.

This isn’t just a side dish. It’s a show-stopper. It’s the elegant side that makes a Tuesday dinner feel like a celebration. Are you ready to make some magic? Let’s do this!

Recipe Overview

• Cuisine: American/French-Inspired
• Category: Side Dish
• Prep Time: 25 minutes
• Cook Time: 1 hour 15 minutes
• Total Time: 1 hour 40 minutes
• Servings: 6-8 people

Do You Love This Recipe Too?

My love affair started at a friend’s spring potluck. I took one bite and my eyes literally went wide. I had to have the recipe!

I begged for it right there at the table. Now, I make it for every single holiday and fancy dinner party. It’s my secret weapon for making people feel loved and well-fed.

It’s that good. The combination is just perfect. It’s rich without being too heavy, and those leeks? They are the sweet, gentle superstar of the whole show.

My Shopping List for This Recipe

This recipe is all about simple, beautiful ingredients. The star players are the potatoes, leeks, and a good onion. That’s it!

You probably have most of this in your kitchen already. The rest is just creamy, cheesy goodness. Let’s check the pantry.

Let’s Get Your Ingredients Ready

Here’s everything you’ll need. Measure it all out first. Trust me, it makes the process so smooth and fun!

• 3 lbs Yukon Gold potatoes, peeled and thinly sliced (about 1/8-inch thick)
• 2 large leeks, white and light green parts only
• 1 large yellow onion
• 4 tablespoons unsalted butter
• 3 cloves garlic, minced
• 1/4 cup all-purpose flour
• 2 1/2 cups whole milk
• 1 cup heavy cream
• 1 1/2 cups shredded Gruyère cheese, divided
• 1/2 cup grated Parmesan cheese
• 1 teaspoon fresh thyme leaves (or 1/2 tsp dried)
• 1/2 teaspoon freshly grated nutmeg
• Salt and freshly ground black pepper, to taste

Bringing This Recipe to Life (Step-by-Step)

Don’t let the layers scare you! We’re going to build this beauty step-by-step. It’s like edible therapy. I promise.

1. Preheat your oven to 375°F (190°C). Butter a 9×13 inch baking dish generously. This is our canvas!
2. Prepare your veggies. Thinly slice the potatoes. Halve the leeks lengthwise, rinse well under water to remove grit, then slice thinly. Slice the onion thinly too.
3. In a large pot or Dutch oven, melt the butter over medium heat. Add the leeks and onion. Cook for 8-10 minutes, stirring, until they are super soft and sweet.
4. Add the garlic and cook for one more minute until fragrant. It will smell amazing.
5. Sprinkle the flour over the cooked veggies. Stir constantly for about 2 minutes. This cooks the flour and makes our sauce.
6. Slowly pour in the milk and cream, whisking constantly to avoid lumps. Bring it to a gentle simmer. The sauce will thicken beautifully.
7. Remove the pot from the heat. Stir in 1 cup of the Gruyère, all of the Parmesan, thyme, nutmeg, salt, and pepper. Taste it! Adjust the seasoning. This sauce is everything.
8. Time to layer! Arrange half of the potato slices in the buttered dish. Pour half of the glorious sauce over them. Repeat with the remaining potatoes and sauce.
9. Sprinkle the last 1/2 cup of Gruyère cheese over the very top. This will get all golden and bubbly.
10. Cover the dish tightly with foil. Bake for 45 minutes. Then, remove the foil and bake for another 25-30 minutes. You want the top to be gorgeously browned and the potatoes to be tender when pierced with a knife.
11. This is the hardest part: let it rest for 15 minutes before serving. This lets the sauce set so you get perfect slices. You can do it!

Fun Variations to Try Next Time

Once you master the classic, play around! It’s a fantastic base for creativity. Here are my favorite twists.

Add some chopped ham or crispy bacon bits between the layers for a heartier version. It’s a full meal then! For another satisfying skillet meal, check out this garlic butter steak and potatoes skillet.

Swap half the Gruyère for a sharp white cheddar. It gives a fantastic tangy kick that’s just incredible.

Throw in a handful of fresh spinach or kale with the leeks for a pop of green and extra nutrients. It’s a sneaky win.

How to Store, Freeze, and Reheat

Got leftovers? Lucky you! They reheat like a dream. Here’s how to keep all that flavor.

Store cooled leftovers in an airtight container in the fridge for 3-4 days. Reheat single portions in the microwave.

For the whole dish, cover with foil and warm in a 350°F oven for 20-30 minutes. You can freeze it before baking! Assemble the dish, wrap it tightly, and freeze for up to 2 months. Thaw in the fridge overnight before baking as directed.

NUTRITION INFORMATION

• Calories: ~420 kcal
• Carbohydrates: 38g
• Protein: 15g
• Fat: 24g
• Saturated Fat: 14g
• Cholesterol: 75mg
• Sodium: 220mg
• Fiber: 4g
• Sugar: 8g

A Quick Q&A on This Recipe

Can I use a different type of potato?

Absolutely! Yukon Golds are my favorite for their buttery texture and they hold their shape. Russets will work too, but they can get a bit more starchy. Just give them a quick rinse after slicing.

My sauce seems too thick/thin. Help!

Don’t panic! If it’s too thick right after making it, just whisk in a splash more milk. If it seems too thin, let it simmer for another minute or two. It will continue to thicken as it bakes with the potatoes, I promise.

Can I make this ahead of time?

You bet! This is a fantastic make-ahead dish. Assemble it completely, cover, and refrigerate for up to 24 hours. Just add about 10 extra minutes to the baking time since it’s going in cold.

And there you have it! My ultimate, go-to, never-fail spectacular side dish. It’s the definition of comfort food with a fancy twist. If you’re craving more cozy, savory soups, our wild mushroom, caramelized onion, and kale soup is another winner.

Every single time I make it, I fall in love all over again. The golden top, the creamy center, the sweet leeks… it’s pure happiness on a plate. I am so excited for you to try it.

I can’t wait to hear how yours turns out! Please leave a comment and a rating below to let me know what you think!