If you’ve ever wished all the soul-soothing flavor of French onion soup could unite with the cheesy, comforting magic of mac & cheese, your culinary dreams have finally come true. This French Onion Soup Mac & Cheese is decadent, cozy, and packed with layers of caramelized onions, creamy Gruyère and cheddar, and an irresistible pasta base. Every bite is a blend of melting cheese, sweet-savory onions, and just enough bite from the pasta—the kind of meal that turns ordinary evenings into something memorable.

French Onion Soup Mac & Cheese Recipe - Recipe Image

Ingredients You’ll Need

The beauty of French Onion Soup Mac & Cheese lies in its simple, easy-to-find ingredients. Each one plays a starring role in the final flavor, whether it’s the sweet depth of caramelized onions or the unmistakable richness of real cheese. Here’s what you’ll need and why:

Butter: Balances richness and helps the onions reach that perfectly golden, caramelized stage.
Olive Oil: Prevents the butter from burning while adding savory flavor.
Yellow Onions: The heart and soul of this dish, they turn deeply sweet and savory with slow cooking.
Salt: Draws moisture from onions and seasons every layer.
Black Pepper: Adds a gentle zing that cuts through the creamy cheeses.
Fresh Thyme: Gives the sauce a subtle, earthy aroma reminiscent of classic French onion soup.
Sugar: Speeds up caramelization and enhances sweetness in the onions.
Balsamic Vinegar: Lends gentle tang and helps deglaze the onion pan for more flavor.
Dry White Wine (optional): Infuses a grown-up depth and complexity (but skip if you’d like).
Elbow Macaroni or Small Pasta Shells: Their shape cradles that luscious cheese sauce.
All-Purpose Flour: Thickens the sauce and gives it a silky texture.
Whole Milk: The creamy base that brings the sauce together.
Beef Broth: Reinforces those French onion soup vibes with hearty, savory notes.
Gruyère Cheese: Delivers nutty, classic French flavor and wonderful melting properties.
Sharp White Cheddar: Offers tang and creaminess for a balanced cheese sauce.
Parmesan Cheese: Punches up the umami and gives you that signature salty finish.
Salt and Pepper (to taste): A final adjuster for perfect seasoning.
Fresh Parsley or Thyme (optional garnish): Brightens up each serving and brings visual appeal.

How to Make French Onion Soup Mac & Cheese

Step 1: Caramelize the Onions

This is where the magic begins! Melt the butter with the olive oil in a large skillet over medium heat, then add the thinly sliced onions, salt, pepper, fresh thyme, and sugar. Take your time letting the onions cook slowly—about 25 to 30 minutes—stirring often. You want them deeply caramelized and golden brown, bringing that unmistakable sweetness and richness to your French Onion Soup Mac & Cheese.

Step 2: Deglaze and Add Depth

Once the onions are beautifully golden, it’s time to boost their flavor even more. Stir in the balsamic vinegar and white wine (if using), making sure to scrape up all those tasty browned bits from the bottom of the pan. Cook for another 2–3 minutes until fragrant. Set aside your caramelized onion masterpiece!

Step 3: Cook the Pasta

Bring a large pot of well-salted water to a boil and cook your elbow macaroni or small shells until just al dente (they’ll finish absorbing flavor in the sauce). Drain and set aside—but don’t rinse, as you want all that starchy surface to help the sauce cling beautifully!

Step 4: Make the Cheese Sauce

In a large pot, melt the butter, then whisk in the flour and cook for 1 minute to make a quick roux. Gradually pour in the milk and beef broth, whisking constantly until the mixture becomes smooth and luxuriously thick, about 4–5 minutes. Now, stir in your caramelized onions and then add Gruyère, white cheddar, and Parmesan, mixing until the cheeses melt into a gorgeous, creamy blanket.

Step 5: Combine and Serve

Gently fold your cooked pasta into the cheese sauce, making sure every nook and cranny is smothered in that decadent French onion delight. Taste and adjust with a little extra salt and pepper if needed. Serve your French Onion Soup Mac & Cheese piping hot, with an extra sprinkle of cheese or herbs for good measure.

How to Serve French Onion Soup Mac & Cheese

Garnishes

To make each bowl extra tempting, scatter some fresh parsley, thyme, or even a little extra grated Gruyère or Parmesan right on top. The herbs offer freshness while the cheese brings melty, golden appeal—every bite tastes like pure comfort with a little bit of flair.

Side Dishes

This dish already packs plenty of richness, so simple is best for sides. Think lightly dressed greens, a crisp apple salad, or a hunk of crusty baguette for soaking up any extra sauce. For deeper indulgence, try roasted vegetables or even a garlicky green bean dish to complement those French onion flavors.

Creative Ways to Present

For a dinner party twist, spoon the mac & cheese into oven-safe ramekins, top with more cheese and a few bread crumbs, then broil for a bubbling, golden crown. Or serve it in a hollowed-out bread bowl for pure showstopper status! You can even garnish with tiny homemade croutons to echo the signature soup topping.

Make Ahead and Storage

Storing Leftovers

If you find yourself with extra French Onion Soup Mac & Cheese, transfer any cooled leftovers to an airtight container and refrigerate for up to four days. Its flavors will deepen, making each reheat just as irresistible as the first time!

Freezing

While the cheese sauce may change texture a bit, you can freeze individual portions in airtight, freezer-safe containers for up to two months. Thaw overnight in the refrigerator before reheating to best maintain that creamy, dreamy bite.

Reheating

For best results, warm leftovers gently in a saucepan over low heat, stirring in a splash of milk or broth to loosen the sauce. You can also reheat in the microwave, pausing to stir halfway through. If baking, cover with foil and heat at 350°F until bubbly.

FAQs

Can I make French Onion Soup Mac & Cheese vegetarian?

Absolutely! Just swap the beef broth for your favorite vegetable broth and you’ll keep all the flavor while skipping the meat component. All the indulgent flavor, none of the compromise!

What’s the best cheese for this recipe?

Gruyère is classic, but you can get creative! A good blend of Gruyère, sharp white cheddar, and Parmesan offers depth and meltability. If you can’t find Gruyère, try Swiss or Fontina for that signature stretch and nutty flavor.

Can I bake French Onion Soup Mac & Cheese?

For a bubbly, golden crust, absolutely! Just transfer the mac and cheese to a baking dish, sprinkle with more cheese or buttered breadcrumbs, and broil until the top is golden and irresistibly crispy. It’s a perfect way to echo the crouton topping from authentic French onion soup.

Is it okay to add meat for extra protein?

Definitely—crisped bacon, pancetta, or even rotisserie chicken can make this dish even heartier. Fold cooked meat into the cheese sauce along with the pasta for a one-pan comfort feast.

What pasta shapes work best besides elbows or shells?

Any short, bite-sized pasta will do the trick! Penne, cavatappi, or rotini are all great alternatives and do an awesome job of holding on to that rich, cheesy sauce.

Final Thoughts

If you’ve been craving a fresh take on classic comfort food, you owe it to yourself to try French Onion Soup Mac & Cheese. With its dreamy, cheesy sauce and golden onions, it truly delivers a restaurant-worthy experience that’s easy enough for a weeknight. Go ahead—make it tonight and let your kitchen be filled with the aroma and delight of this unforgettable mash-up!

French Onion Soup Mac & Cheese Recipe

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4.8 from 28 reviews

Author: Emma
Total Time: 50 minutes
Yield: 6 servings 1x
Diet: Non-Vegetarian

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Description

Indulge in the ultimate comfort food with this French Onion Soup Mac & Cheese recipe. Caramelized onions, three types of cheese, and tender pasta come together in a decadent fusion of flavors. Perfect for a cozy night in or a special dinner with loved ones.

Ingredients

Scale

Caramelized Onions:

2 tablespoons butter
2 tablespoons olive oil
3 large yellow onions (thinly sliced)
1/2 teaspoon salt
1/4 teaspoon black pepper
1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried)
1/2 teaspoon sugar
1 tablespoon balsamic vinegar
1/4 cup dry white wine (optional)

Mac & Cheese:

12 ounces elbow macaroni or small pasta shells
2 tablespoons all-purpose flour
2 cups whole milk
1 cup beef broth
2 cups shredded Gruyère cheese
1 cup shredded sharp white cheddar
1/2 cup grated Parmesan cheese
Salt and pepper to taste
Fresh parsley or thyme for garnish (optional)

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Instructions

Caramelized Onions: In a large skillet, melt butter with olive oil over medium heat. Add onions, salt, pepper, thyme, and sugar. Cook for 25–30 minutes until caramelized. Stir in balsamic vinegar and wine. Set aside.
Mac & Cheese: Cook pasta according to package instructions. In a pot, melt butter, whisk in flour, then gradually add milk and broth. Stir in caramelized onions and cheeses until creamy. Fold in pasta and adjust seasoning.
Serve hot, garnished with extra cheese or herbs if desired.

Notes

For a baked version, transfer mac and cheese to a baking dish, top with additional cheese or breadcrumbs, and broil until golden and bubbly.
You can substitute vegetable broth to make it vegetarian.

Prep Time: 15 minutes
Cook Time: 35 minutes
Category: Main Course
Method: Stovetop
Cuisine: American-French Fusion