French Onion Soup Mac & Cheese Recipe

Introduction

French Onion Soup Mac & Cheese is a comforting twist on two classic dishes. Featuring rich caramelized onions, a blend of cheeses, and a crispy breadcrumb topping, this recipe offers deep flavor in every creamy bite.

Ingredients

• 12 ounces elbow macaroni
• 3 large yellow onions, thinly sliced
• 2 tablespoons olive oil
• 3 tablespoons butter
• 2 cloves garlic, minced
• 3 tablespoons flour
• 2 cups vegetable broth
• 2 cups whole milk
• 1/2 cup heavy cream
• 2 cups Gruyère cheese, shredded
• 1 cup sharp cheddar cheese, shredded
• 1 cup mozzarella cheese, shredded
• 1 teaspoon salt
• 1/2 teaspoon black pepper
• 1 teaspoon fresh thyme (or 1/2 teaspoon dried)
• 1 cup breadcrumbs
• 1/2 cup Parmesan cheese, grated

Instructions

1. Step 1: Preheat your oven to 375°F (190°C) and butter a baking dish to prepare for baking.
2. Step 2: In a skillet, heat olive oil and 1 tablespoon of butter over medium heat. Add the sliced onions and cook, stirring often, until caramelized, about 25–30 minutes. Stir in the minced garlic and thyme during the last couple of minutes.
3. Step 3: Add the remaining 2 tablespoons of butter to the skillet. Stir in the flour and cook for 1–2 minutes to create a roux. Slowly whisk in the vegetable broth, then the milk and heavy cream, stirring until the sauce is smooth.
4. Step 4: Add Gruyère, cheddar, and mozzarella cheeses to the sauce and stir until completely melted. Season with salt and black pepper to taste.
5. Step 5: Cook the elbow macaroni according to package instructions until al dente. Drain and toss the pasta with the cheese sauce and caramelized onions.
6. Step 6: Transfer the mac and cheese mixture into the prepared baking dish. In a small bowl, combine breadcrumbs and grated Parmesan, then sprinkle evenly over the top.
7. Step 7: Bake in the preheated oven for 20–25 minutes, or until the topping is bubbly and golden brown.
8. Step 8: Remove from oven and let the dish rest for 5 minutes. Garnish with extra thyme if desired, then serve hot and enjoy.

Tips & Variations

• For a deeper onion flavor, add a splash of dry white wine to the caramelized onions before making the roux.
• Use a mix of cheeses you prefer; Gruyère can be swapped for Swiss or fontina for a different taste.
• If you like a crunchy topping, toast the breadcrumbs in a little butter before sprinkling.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently in the oven or microwave to keep the topping crisp. Adding a splash of milk or cream before reheating can help maintain creaminess.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I use a different type of pasta?

Yes, feel free to substitute elbow macaroni with cavatappi, shells, or any small pasta shape that holds sauce well.

Is it possible to make this recipe vegetarian?

Absolutely. This recipe already uses vegetable broth for a vegetarian version. Just ensure the cheeses you use do not contain animal rennet if strict vegetarianism is a concern.

French Onion Soup Mac & Cheese Recipe

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★★★★★

4.8 from 149 reviews

A rich and comforting twist on classic mac & cheese inspired by French onion soup, featuring caramelized onions, a creamy cheese sauce with Gruyère, cheddar, and mozzarella, topped with a crunchy Parmesan breadcrumb crust and baked to golden perfection.

• Author: Emma
• Prep Time: 15 minutes
• Cook Time: 45 minutes
• Total Time: 1 hour
• Yield: 6 servings 1x
• Category: Main Course
• Method: Baking
• Cuisine: American
• Diet: Vegetarian

Ingredients

Scale 1x2x3x

Pasta

• 12 ounces elbow macaroni

Onion Mixture

• 3 large yellow onions, thinly sliced
• 2 tablespoons olive oil
• 3 tablespoons butter (divided)
• 2 cloves garlic, minced
• 1 teaspoon fresh thyme (or 1/2 teaspoon dried thyme)

Sauce

• 3 tablespoons flour
• 2 cups vegetable broth
• 2 cups whole milk
• 1/2 cup heavy cream
• 2 cups shredded Gruyère cheese
• 1 cup shredded sharp cheddar cheese
• 1 cup shredded mozzarella cheese
• 1 teaspoon salt
• 1/2 teaspoon black pepper

Topping

• 1 cup breadcrumbs
• 1/2 cup grated Parmesan cheese

Instructions

1. Preheat Oven and Prepare Dish: Preheat your oven to 375°F (190°C) and butter a baking dish to prevent sticking.
2. Caramelize Onions: Heat olive oil and 1 tablespoon of butter in a skillet over medium heat. Add the thinly sliced onions and cook for 25–30 minutes, stirring often, until the onions are deeply caramelized and golden brown. Stir in minced garlic and thyme towards the end to infuse flavor.
3. Make the Roux and Sauce: Add the remaining butter to the skillet with the onions. Stir in flour to create a roux, cooking briefly to remove the raw flour taste. Slowly whisk in the vegetable broth, followed by the whole milk and heavy cream, ensuring the sauce becomes smooth and thickened.
4. Add Cheese and Season: Stir in the shredded Gruyère, sharp cheddar, and mozzarella cheeses until fully melted and blended into the sauce. Season the cheese sauce with salt and black pepper to taste.
5. Combine Pasta and Sauce: Cook elbow macaroni until al dente according to package instructions. Drain and toss the pasta into the cheese sauce along with the caramelized onions, mixing well to evenly coat everything.
6. Prepare Topping and Assemble: In a small bowl, combine breadcrumbs with grated Parmesan cheese. Transfer the mac & cheese mixture into the prepared baking dish and evenly sprinkle the breadcrumb-Parmesan mixture on top.
7. Bake: Bake in the preheated oven for 20–25 minutes, or until the top is bubbly, golden brown, and crispy.
8. Rest and Serve: Remove from the oven and let rest for 5 minutes. Garnish with fresh thyme if desired, then serve hot and enjoy your French Onion Soup Mac & Cheese.

Notes

• Caramelizing onions slowly is key to developing deep flavor; patience is important during this step.
• Using a blend of Gruyère, sharp cheddar, and mozzarella creates a balanced cheese sauce with creaminess and tang.
• For a vegetarian version, ensure the vegetable broth is used instead of beef broth.
• Breadcrumb topping adds delightful crunch; you can substitute panko breadcrumbs for extra crispiness.
• Leftovers can be refrigerated for up to 3 days and reheated in the oven for best results.

Keywords: French onion soup, mac and cheese, caramelized onions, Gruyère cheese, baked mac and cheese, comfort food, creamy cheese sauce