French Onion Soup Mac & Cheese Recipe
This French Onion Soup Mac & Cheese combines the rich, caramelized flavors of classic French onion soup with creamy, cheesy macaroni for a comforting and indulgent twist on two beloved dishes. The slow-cooked onions and aromatic thyme infuse the creamy cheese sauce, which is baked to golden perfection with a crunchy breadcrumb and Parmesan topping.
- Prep Time: 15 minutes
- Cook Time: 55 minutes
- Total Time: 1 hour 10 minutes
- Yield: 6 servings 1x
- Category: Main Course
- Method: Baking
- Cuisine: French-American
- Diet: Vegetarian
Ingredients
Scale
Pasta
- 12 ounces elbow macaroni
Onions and Aromatics
- 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 Gruyère cheese, shredded
- 1 cup sharp cheddar cheese, shredded
- 1 cup mozzarella cheese, shredded
- 1 teaspoon salt
- 1/2 teaspoon black pepper
Topping
- 1 cup breadcrumbs
- 1/2 cup Parmesan cheese, grated
Instructions
- Preheat Your Equipment: Preheat your oven to 375°F (190°C) and generously butter a baking dish to prevent sticking.
- Caramelize Onions: Heat olive oil and 1 tablespoon of butter in a large skillet over medium heat. Add the thinly sliced onions and cook, stirring often, until they become deeply caramelized and golden brown, which takes about 25–30 minutes. Then stir in the minced garlic and thyme, cooking for about 1 more minute until fragrant.
- Make the Roux and Sauce: To the skillet with the onions, add the remaining butter and let it melt. Stir in the flour to create a roux, cooking for 1–2 minutes while stirring to remove the raw flour taste. Slowly whisk in the vegetable broth, followed by the milk and heavy cream, ensuring the mixture is smooth and thickened.
- Add the Cheese: Stir in the shredded Gruyère, cheddar, and mozzarella cheeses until melted and fully incorporated into the sauce. Season with salt and black pepper to taste.
- Combine Pasta and Sauce: Toss the cooked al dente macaroni noodles with the cheese sauce and caramelized onions, making sure everything is evenly coated and combined.
- Assemble in Baking Dish: Transfer the mac and cheese mixture into the prepared buttered baking dish. In a small bowl, mix the breadcrumbs with Parmesan cheese. Evenly sprinkle this topping over the mac and cheese.
- Bake: Place the baking dish in the preheated oven and bake for 20–25 minutes, or until the top is golden brown and bubbly.
- Serve: Remove from the oven and let the dish rest for 5 minutes. Garnish with extra fresh thyme if desired and serve hot for a comforting meal.
Notes
- For the best flavor, allow the onions to caramelize slowly and patiently; rushing this step will result in less depth of flavor.
- You can substitute vegetable broth with beef broth for a richer taste if not vegetarian.
- To make ahead, assemble the dish, cover, and refrigerate up to 24 hours before baking.
- Use day-old breadcrumbs for a crisper topping.
- For a gluten-free version, use gluten-free flour and gluten-free breadcrumbs.
Keywords: French Onion Soup, Mac and Cheese, Caramelized Onions, Comfort Food, Baked Pasta, Cheese Sauce
