French Onion Soup Mac & Cheese Recipe

Introduction

French onion soup mac & cheese is a comforting twist on two classic favorites. This dish combines caramelized onions and rich cheeses with tender macaroni, delivering a creamy, flavorful meal that’s perfect for cozy evenings.

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. Cook until they turn golden brown and develop a rich, sweet flavor.
2. Step 2: Sprinkle the flour over the caramelized onions and stir well to coat. Gradually whisk in the broth and half-and-half or cream until the mixture is smooth and begins to thicken. Add minced garlic and dried thyme, then stir in Gruyère and cheddar cheeses until melted 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 the sauce needs loosening later.
4. Step 4: Mix the cooked macaroni into the cheese sauce, making sure every piece is evenly coated with the creamy sauce.
5. Step 5: Transfer the mac & cheese to an oven-safe dish. Top with extra grated cheese and toasted baguette slices if using. Broil briefly until the topping is bubbly and golden brown, watching carefully to prevent burning.

Tips & Variations

• For a vegetarian version, substitute vegetable broth for beef broth without affecting the flavor too much.
• Use half-and-half for a lighter sauce or heavy cream for extra richness.
• Adding a pinch of smoked paprika can introduce a subtle smoky note that complements the onion flavor.
• If the sauce is too thick, loosen it with reserved pasta water a little at a time until you reach the desired consistency.
• Serve with a simple green salad to balance the richness of the dish.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently in the microwave or on the stovetop with a splash of broth or cream to restore creaminess. For best texture, avoid reheating multiple times.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare the caramelized onions ahead of time?

Yes, caramelized onions can be made a day in advance and refrigerated. Reheat gently before continuing with the recipe.

What can I use instead of Gruyère cheese?

Swiss cheese or a good-quality mozzarella can be used as alternatives, though Gruyère adds a distinctive nutty flavor that complements the dish.

French Onion Soup Mac & Cheese Recipe

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★★★★★

4.9 from 125 reviews

This French Onion Soup Mac & Cheese is a decadent fusion dish combining the rich, caramelized flavors of traditional French onion soup with creamy, cheesy macaroni. Tenderly caramelized onions create a deep, savory base which is transformed into a luscious cheese sauce with Gruyère and sharp white cheddar, enveloping perfectly cooked elbow macaroni. Finished under the broiler with extra cheese and toasted baguette slices, it delivers a delightful crispy topping reminiscent of a classic French onion soup crouton. This comforting and flavorful dish is perfect for cozy dinners or special occasions.

• Author: Luna
• Prep Time: 15 minutes
• Cook Time: 50 minutes
• Total Time: 1 hour 5 minutes
• Yield: 6 servings 1x
• Category: Main Course
• Method: Stovetop
• Cuisine: French-American
• Diet: Vegetarian

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

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 Topping

• 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: In a large skillet or saucepan, melt the butter over low heat. Add the thinly sliced yellow onions and cook slowly for 30-40 minutes, stirring occasionally, until they turn golden brown and develop a rich, sweet flavor. This deep caramelization forms the flavorful base of the dish.
2. Make the cheese sauce: Sprinkle the flour evenly over the caramelized onions, stirring well to coat all the onions. Gradually whisk in the beef or vegetable broth and the half-and-half or heavy cream, stirring continuously until the mixture becomes smooth and thickened. Add the minced garlic and dried thyme, then melt in the Gruyère and sharp white cheddar cheeses, stirring gently until the sauce is creamy and fully combined. Season with salt and freshly ground black pepper to taste.
3. Cook the macaroni: Bring a large pot of salted water to a boil and cook the elbow macaroni according to package instructions until al dente, about 7-8 minutes. Drain the pasta well but reserve a small amount of pasta water in case the sauce needs loosening later.
4. Combine pasta and sauce: Fold the cooked macaroni into the cheese and onion sauce, making sure every piece is thoroughly coated with the luscious, velvety sauce. If the sauce seems too thick, add a splash of the reserved pasta water to reach your desired consistency.
5. Bake or broil optional topping: Preheat your oven’s broiler. Transfer the mac & cheese to an oven-safe baking dish. Top the dish with the extra grated cheese and optionally arrange toasted baguette slices on top to replicate the classic French onion soup crouton. Place under the broiler for 2-4 minutes until the cheese topping is bubbly and golden brown. Watch carefully to prevent burning. Remove from oven and serve immediately.

Notes

• For a vegetarian version, use vegetable broth instead of beef broth.
• You can substitute half-and-half or heavy cream depending on your preference for richness.
• Keep a close eye when broiling to avoid burning the cheese or bread topping.
• Gruyère cheese is essential for the authentic French onion flavor; if unavailable, consider substituting with a similar Swiss cheese.
• To save time, caramelized onions can be prepared in advance and refrigerated.

Keywords: French onion soup mac and cheese, caramelized onion mac and cheese, cheesy macaroni, Gruyère mac and cheese, comfort food recipe, French fusion recipe