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Recipes

French Onion Soup + Mac and Cheese: Together at Last

It sure is tasty when two classic comfort foods come together as one.

French onion soup is one of my all-time favorite comfort foods. And mac and cheese is also one of my all-time favorite comfort foods. 

French onion soup is savory, a touch sweet, and full of ooey, gooey cheese. Mac and cheese is rich, creamy, and. . . also full of ooey, gooey cheese. 

I’m sensing a theme here.

So, French onion mac and cheese? How bad can that be? 

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Turns out the combination of the two works really well. Think about it! Loads of onions get caramelized low and slow in butter and fresh thyme. Macaroni gets coated in a sauce made with both Monterey Jack (for meltiness) and Gruyère (for French onion soupiness). Stirred together and served in individual soup crocks? I mean, come on. It’s as comforting as a warm hug. 

But wait, there’s more. 

We had to pay a final homage to French onion soup which meant a trip under the broiler. With croutons. And more cheese. Now we’re talking.

I know I said warm hug, but this French onion mac and cheese is more weighted blanket level of comfort. Which makes sense because you’ll definitely need a nap after eating it.

French Onion Soup Mac & Cheese

Serves 6

  • 12 ounces elbow macaroni
  • ½ teaspoon table salt, plus salt for cooking pasta
  • 2 tablespoons unsalted butter
  • 3 pounds onions, halved and sliced thin
  • 4 sprigs fresh thyme
  • 1 bay leaf
  • ½ teaspoon sugar
  • 1 cup beef broth
  • 3 tablespoons all-purpose flour
  • 2½ cups milk 
  • 8 ounces Monterey Jack cheese, shredded (2 cups), divided
  • 8 ounces Gruyère cheese, shredded (2⅔ cups), divided
  • 1 teaspoon Dijon mustard


1. Adjust oven rack to upper-middle position and heat oven to 450 degrees. Bring 4 quarts water to boil in Dutch oven. Add macaroni and 1 tablespoon salt and cook, stirring often, until tender. Drain macaroni and set aside in colander. 

2. Add butter to now-empty pot and melt over medium-high heat. Stir in onions, thyme, salt, and sugar. Cover and cook, stirring occasionally, until onions release their liquid and are uniformly translucent, about 20 minutes.

3. Uncover and cook until liquid has evaporated and browned bits start to form on bottom of pot, 5 to 10 minutes. Reduce heat to medium and continue to cook, uncovered, until onions are caramel colored, 30 to 40 minutes longer, stirring and scraping with wooden spoon as browned bits form on bottom of pot and spreading onions into even layer after stirring. (If onions or browned bits begin to scorch, reduce heat to medium-low.)

4. Discard thyme sprigs and bay leaf. Stir in broth, scraping up any browned bits, and cook until slightly thickened, about 1 minute. Whisk in flour and cook for 1 minute. Slowly whisk in milk until smooth. Bring mixture to boil, adjust heat to medium, and cook, whisking occasionally, until thickened to consistency of heavy cream, about 5 minutes. 

5. Add 6 ounces Monterey Jack cheese, 6 ounces Gruyère, and mustard, stirring constantly, until cheese is completely melted, about 1 minute. Add macaroni and cook over medium-low heat, stirring constantly, until steaming and heated through, about 6 minutes.

6.Transfer to 13 by 9-inch baking dish and sprinkle with remaining 2 ounces Monterey Jack and remaining 2 ounces Gruyère. Bake until spotty brown and filling is bubbling, 15 to 20 minutes. Let rest for 5 minutes. Serve.