Description
This indulgent French Onion Soup Mac & Cheese combines the rich, caramelized flavors of classic French onion soup with creamy, cheesy macaroni. Layers of sweet, slow-cooked onions and a blend of Gruyère, cheddar, and mozzarella cheeses create an irresistible comfort food that’s baked to bubbly perfection with a golden, crispy Parmesan breadcrumb topping. Perfect for a cozy dinner that elevates traditional mac & cheese with sophisticated flavors.
Ingredients
Scale
Pasta
- 12 ounces Elbow Macaroni
Onion Base
- 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)
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
- Preheat and Prepare Dish: Preheat your oven to 375°F (190°C). Butter a baking dish to prevent sticking and prepare it for the mac & cheese mixture.
- Caramelize Onions: In a skillet, heat olive oil and 1 tablespoon of butter over medium heat. Add the thinly sliced onions and cook slowly, stirring often, for 25 to 30 minutes until they are deeply caramelized and golden brown. Stir in the minced garlic and thyme during the last minute of cooking to release their flavors.
- Make the Sauce Base: Add the remaining butter to the skillet. Sprinkle in the flour and stir constantly to create a roux. Gradually whisk in the vegetable broth, followed by the milk and heavy cream, ensuring the mixture is smooth with no lumps.
- Add Cheeses and Season: Stir in the Gruyère, sharp cheddar, and mozzarella cheeses into the sauce until fully melted and creamy. Season the sauce with salt and black pepper. Then, mix the cooked macaroni with the cheese sauce and caramelized onions until well combined.
- Assemble the Dish: Transfer the mac & cheese mixture into the prepared baking dish. In a small bowl, mix the breadcrumbs with the grated Parmesan cheese and sprinkle this evenly over the top of the mac & cheese for a crunchy topping.
- Bake: Place the dish in the preheated oven and bake for 20 to 25 minutes, or until the topping is golden brown and the sauce is bubbly around the edges.
- Rest and Serve: Remove the dish from the oven and let it rest for 5 minutes to thicken slightly. Garnish with fresh thyme if desired and serve hot for a comforting and flavorful meal.
Notes
- Use freshly grated cheeses for the best melt and flavor.
- Caramelizing onions slowly is key to developing the deep, sweet flavor that mimics French onion soup.
- For a richer sauce, whole milk and heavy cream combination creates excellent creaminess.
- To make ahead, assemble everything up to step 5, cover, and refrigerate. Bake just before serving.
- Gluten-free option: Use gluten-free flour and breadcrumbs as substitutes.
