French Onion Soup Mac & Cheese Recipe

Introduction

French onion soup mac & cheese is a comforting twist on two classic favorites. It combines caramelized onions, rich cheese sauce, and tender pasta to create a deeply flavorful dish that’s perfect for cozy evenings. This recipe brings the essence of French onion soup into a creamy, cheesy macaroni bake.

Ingredients

• 3 large yellow onions, thinly sliced
• 3 tbsp butter
• 2 cloves garlic, minced
• 1 tsp dried thyme
• Salt and freshly ground black pepper, to taste
• 3 tbsp all-purpose flour
• 4 cups beef broth (or vegetable broth for vegetarian option)
• 1 cup half-and-half or heavy cream
• 1 ½ cups grated Gruyère cheese
• 1 cup sharp white cheddar cheese, grated
• 12 oz elbow macaroni
• Optional: French bread or baguette slices for toasting
• Extra grated cheese for topping (about ½ cup)

Instructions

1. Step 1: Slowly cook the thinly sliced yellow onions in butter over low heat for 30-40 minutes, stirring occasionally, until they are golden brown and have a rich, sweet flavor.
2. Step 2: Sprinkle the flour over the caramelized onions and stir well to coat. Gradually whisk in the beef or vegetable broth and half-and-half or heavy cream until the mixture is smooth and thickened. Add the minced garlic and dried thyme, then melt in the Gruyère and sharp white cheddar cheeses until creamy and combined. Season with salt and pepper to taste.
3. Step 3: Boil the elbow macaroni according to package instructions until al dente. Drain well, reserving a small amount of pasta water in case you need to loosen the sauce later.
4. Step 4: Mix the cooked macaroni into the cheese sauce, ensuring every piece is evenly coated with the velvety sauce.
5. Step 5: Transfer the mac & cheese to an oven-safe dish. Top with extra grated cheese and toasted baguette slices if desired. Broil briefly until the top is bubbly and golden brown, mimicking the classic French onion soup crouton finish. Watch carefully to avoid burning.

Tips & Variations

• For a vegetarian option, use vegetable broth instead of beef broth without compromising flavor.
• If you prefer a smoother sauce, blend the caramelized onion mixture before adding the cheese.
• Try adding a splash of white wine when cooking the onions for extra depth of flavor.
• Use a mix of cheeses like Gruyère and sharp cheddar to balance creaminess and sharpness.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. To reheat, warm gently on the stovetop or in the microwave, adding a splash of milk or broth if the sauce has thickened too much. For best texture, avoid reheating in the oven, which may dry it out.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this dish ahead of time?

Yes, you can prepare the mac & cheese up to the step before broiling. Store it in the fridge and broil just before serving to maintain the crispy topping.

What can I use instead of Gruyère cheese?

Swiss cheese or Emmental are good substitutes as they melt well and offer a similar nutty flavor.

French Onion Soup Mac & Cheese Recipe

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★★★★★

4.6 from 77 reviews

This French onion soup mac & cheese recipe combines the rich, caramelized flavors of classic French onion soup with creamy, cheesy macaroni, creating a comforting and elevated twist on traditional mac & cheese. Slow-cooked onions, a savory cheese sauce with Gruyère and sharp white cheddar, and a crispy, cheesy topping give this dish a sophisticated yet nostalgic appeal.

• Author: Cleo
• Prep Time: 15 minutes
• Cook Time: 45 minutes
• Total Time: 1 hour
• Yield: 6 servings 1x
• Category: Main Dish
• Method: Stovetop
• Cuisine: French-American

Ingredients

Scale 1x2x3x

Onion Base

• 3 large yellow onions, thinly sliced
• 3 tbsp butter
• 2 cloves garlic, minced
• 1 tsp dried thyme
• Salt and freshly ground black pepper, to taste

Cheese Sauce

• 3 tbsp all-purpose flour
• 4 cups beef broth (or vegetable broth for vegetarian option)
• 1 cup half-and-half or heavy cream
• 1 ½ cups grated Gruyère cheese
• 1 cup sharp white cheddar cheese, grated

Pasta and Toppings

• 12 oz elbow macaroni
• Optional: French bread or baguette slices for toasting
• Extra grated cheese for topping (about ½ cup)

Instructions

1. Caramelize the onions: Slowly cook thinly sliced yellow onions in butter over low heat for 30-40 minutes, stirring occasionally, until they turn golden brown and develop a rich, sweet flavor.
2. Make the cheese sauce: Sprinkle flour over the caramelized onions and stir well to coat. Gradually whisk in the beef or vegetable broth and half-and-half or heavy cream until the mixture is smooth and thickened. Add minced garlic and dried thyme, then melt in Gruyère and sharp white cheddar cheeses until creamy and combined. Season with salt and pepper to taste.
3. Cook the macaroni: Boil elbow macaroni according to package instructions until al dente. Drain well, reserving a small amount of pasta water in case the sauce needs to be loosened later.
4. Combine pasta and sauce: Mix the cooked macaroni into the cheese sauce, ensuring every piece is evenly coated with the luscious, velvety sauce.
5. Bake or broil optional topping: Transfer the mac & cheese to an oven-safe dish. Top with extra grated cheese and toasted baguette slices if desired. Broil briefly until the top is bubbly and golden brown, mimicking the classic French onion soup crouton finish. Watch carefully to avoid burning.

Notes

• For a vegetarian version, substitute beef broth with vegetable broth.
• Use half-and-half for a lighter sauce or heavy cream for extra richness.
• Keep stirring the onions frequently while caramelizing to prevent burning.
• Reserved pasta water can be used to adjust sauce consistency if it becomes too thick.
• Broil topping under close watch to prevent burning and achieve a perfect golden crust.

Keywords: French onion soup mac and cheese, caramelized onion mac and cheese, Gruyère mac and cheese, comfort food, cheesy pasta casserole