Description
A rich and cozy baked mac and cheese inspired by classic onion soup, made with deeply caramelized onions, a creamy blend of Gruyère, white cheddar, mozzarella, and Parmesan, then finished with buttery toasted breadcrumbs.
Ingredients
Scale
- 16 ounces elbow macaroni
- 4 tablespoons unsalted butter, divided
- 2 tablespoons olive oil
- 3 large yellow onions, thinly sliced
- 3 cloves garlic, minced
- 1 teaspoon kosher salt, plus more for the pasta water
- 1/2 teaspoon black pepper
- 1 teaspoon fresh thyme leaves, plus more for garnish
- 2 tablespoons all-purpose flour
- 1 teaspoon Dijon mustard
- 1 cup low-sodium vegetable broth
- 2 cups whole milk
- 1 cup heavy cream
- 2 cups shredded Gruyère cheese
- 2 cups shredded sharp white cheddar cheese
- 1 cup shredded mozzarella cheese
- 1/2 cup finely grated Parmesan cheese
- 1/2 cup panko breadcrumbs
Instructions
- Preheat the oven to 400°F and lightly butter a 9 x 13-inch baking dish.
- Bring a large pot of salted water to a boil and cook the elbow macaroni until just al dente, about 1 to 2 minutes less than package directions. Drain and set aside.
- In a bowl, combine the Gruyère cheese, sharp white cheddar cheese, mozzarella cheese, and Parmesan cheese.
- In a large skillet or Dutch oven, heat 2 tablespoons of the butter with the olive oil over medium-low heat. Add the sliced onions, kosher salt, black pepper, and fresh thyme leaves. Cook, stirring often, for 30 to 35 minutes until deeply golden and soft.
- Stir in the garlic and cook for 1 minute. Sprinkle in the flour and cook, stirring constantly, for 1 minute more.
- Slowly whisk in the vegetable broth, then add the whole milk, heavy cream, and Dijon mustard. Simmer for 3 to 4 minutes until slightly thickened.
- Lower the heat and stir in the Gruyère cheese, sharp white cheddar cheese, mozzarella cheese, and Parmesan cheese a handful at a time until melted and smooth.
- Fold in the cooked macaroni and stir until evenly coated. Transfer the mixture to the prepared baking dish.
- Melt the remaining 2 tablespoons butter and toss with the panko breadcrumbs. Sprinkle the breadcrumbs evenly over the pasta.
- Bake for 15 to 20 minutes until bubbling and golden on top. Let rest for 5 to 10 minutes, garnish with extra thyme, and serve warm.
Notes
- Cook the onions low and slow for the best sweet, deep flavor.
- Shred the cheese from blocks for a smoother sauce.
- Do not overcook the pasta before baking, because it will continue cooking in the oven.
- Add a splash of milk when reheating leftovers to bring back the creamy texture.
Nutrition
- Serving Size: 1 serving
- Calories: 780
- Sugar: 8g
- Sodium: 620mg
- Fat: 43g
- Saturated Fat: 24g
- Unsaturated Fat: 15g
- Trans Fat: 0.5g
- Carbohydrates: 62g
- Fiber: 3g
- Protein: 31g
- Cholesterol: 120mg
Keywords: onion soup mac and cheese, french onion pasta bake, baked macaroni and cheese, caramelized onion mac and cheese, gruyere mac and cheese