French Onion Soup Mac & Cheese Recipe
This French onion soup mac & cheese combines the rich, caramelized flavors of traditional French onion soup with creamy, cheesy macaroni. Caramelized onions create a deep, savory base that is blended with Gruyère and sharp white cheddar cheeses to form a luscious sauce. The macaroni is then mixed in and optionally topped with toasted baguette slices and extra cheese, broiled to golden perfection for a comforting, flavorful twist on classic mac & cheese.
- Prep Time: 15 minutes
- Cook Time: 45 minutes
- Total Time: 1 hour
- Yield: 6 servings 1x
- Category: Main Course
- Method: Stovetop
- Cuisine: French-American
- Diet: Vegetarian
Ingredients
Scale
Onion and Base
- 3 large yellow onions, thinly sliced
- 3 tbsp butter
- 2 cloves garlic, minced
- 1 tsp dried thyme
- Salt and freshly ground black pepper, to taste
Sauce
- 3 tbsp all-purpose flour
- 4 cups beef broth (or vegetable broth for vegetarian option)
- 1 cup half-and-half or heavy cream
- 1 ½ cups grated Gruyère cheese
- 1 cup sharp white cheddar cheese, grated
Pasta and Topping
- 12 oz elbow macaroni
- Optional: French bread or baguette slices for toasting
- Extra grated cheese for topping (about ½ cup)
Instructions
- Caramelize the Onions: Slowly cook the thinly sliced yellow onions in butter over low heat for 30-40 minutes, stirring occasionally. This process allows the onions to turn golden brown and develop a rich, sweet flavor essential for the dish.
- Make the Cheese Sauce: Sprinkle flour over the caramelized onions and stir well to coat. Gradually whisk in the beef or vegetable broth and half-and-half or heavy cream until the mixture is smooth and thickened. Add minced garlic and dried thyme, then melt in Gruyère and sharp white cheddar cheeses, stirring until creamy and fully combined. Season with salt and freshly ground black pepper to taste.
- Cook the Macaroni: Boil the elbow macaroni according to the package instructions until al dente. Drain the pasta well, reserving a small amount of pasta water in case it is needed to loosen the cheese sauce later.
- Combine Pasta and Sauce: Mix the cooked macaroni into the cheese sauce thoroughly, ensuring every macaroni piece is coated evenly with the luscious, velvety cheese and onion sauce.
- Bake or Broil Optional Topping: Transfer the mac & cheese mixture into an oven-safe dish. Top with extra grated cheese and toasted baguette slices if desired. Broil briefly until the top is bubbly and golden brown, mimicking the classic French onion soup’s crouton finish. Watch carefully to prevent burning.
Notes
- For a vegetarian version, use vegetable broth instead of beef broth.
- Be sure to stir onions frequently while caramelizing to avoid burning and ensure even browning.
- Using freshly grated cheese yields a better melt and texture than pre-shredded options.
- The reserved pasta water can help loosen the sauce if it becomes too thick when combining with pasta.
- Broiling the topping is optional but adds a delightful crispy, golden contrast to the creamy mac & cheese.
Keywords: French onion soup, mac and cheese, Gruyère cheese, caramelized onions, comfort food, cheesy pasta, baked mac and cheese, French cuisine inspired
