Description
This decadent French Onion Soup Mac & Cheese blends the rich, caramelized flavors of traditional French onion soup with creamy, cheesy macaroni. Slowly caramelized onions develop deep sweetness, combined with a savory beef broth cheese sauce featuring Gruyère, sharp cheddar, and Parmesan. Perfect as a comforting meal, this dish delivers layers of savory goodness with an optional crisp, cheesy baguette topping.
Ingredients
Scale
Macaroni
- 8 oz elbow macaroni
Onion Soup Base
- 4 large onions, thinly sliced
- 4 tablespoons butter
- 2 cloves garlic, minced
- 2 tablespoons all-purpose flour
- 3 cups beef broth
- 1 teaspoon fresh thyme leaves (or 1/2 tsp dried thyme)
- Salt and pepper to taste
Cheese Sauce
- 1 cup shredded Gruyère cheese
- 1 cup shredded sharp cheddar cheese
- 1/2 cup grated Parmesan cheese
Optional Topping
- Sliced baguette
- Extra Gruyère cheese for topping
Instructions
- Cook Macaroni: Cook elbow macaroni according to package directions until al dente. Drain well and set aside to incorporate later with the cheese sauce.
- Caramelize Onions: In a large skillet over medium heat, melt the butter. Add the thinly sliced onions and cook slowly, stirring occasionally, allowing them to become deeply caramelized and golden brown. This process takes about 30 to 40 minutes to develop a rich, sweet flavor.
- Add Garlic: Once onions are caramelized, stir in the minced garlic and cook for an additional minute until fragrant.
- Make Roux: Sprinkle the all-purpose flour evenly over the onions and stir thoroughly to coat. Cook the mixture for about 2 minutes to eliminate the raw flour taste and help thicken the sauce.
- Incorporate Broth and Herbs: Gradually whisk in the beef broth and add the thyme leaves. Simmer the mixture for approximately 5 minutes, continuing to stir, until the sauce thickens slightly and flavors meld together.
- Add Cheese: Reduce the heat to low and stir in the Gruyère, sharp cheddar, and Parmesan cheeses. Continue to stir until all the cheese has melted completely and the sauce becomes smooth and creamy.
- Combine Macaroni and Sauce: Add the cooked elbow macaroni to the cheese-onion sauce and mix until well combined. Season the mac and cheese with salt and freshly ground black pepper to taste.
- Optional Broil with Baguette Topping: For a crispy, golden crust, transfer the mac and cheese to a baking dish. Top with sliced baguette and extra Gruyère cheese. Place under a broiler briefly until the topping turns bubbly and golden brown, watching carefully to prevent burning.
- Serve and Enjoy: Serve the French Onion Soup Mac & Cheese hot for a comforting, richly flavored meal.
Notes
- Caramelizing onions low and slow is key for deep flavor—do not rush this step.
- You can substitute beef broth with vegetable broth for a lighter flavor.
- Gruyère is essential for its nutty flavor; avoid substitutions for best results.
- The optional broiling step adds a crispy texture but can be skipped for a creamier macaroni.
- Leftovers reheat well on the stovetop or microwave; add a splash of broth or milk to loosen the sauce.
