French Onion Mac Cheese Bake

Featured in: Warm Comfort Bites

This comforting dish combines tender elbow macaroni with deeply caramelized onions and a rich blend of Gruyère, cheddar, and Parmesan cheeses. Cooked all in one pot, it’s simmered with vegetable broth and milk until creamy, then baked with buttery breadcrumbs for a crispy topping. Aromatic garlic and thyme add subtle depth, while the final golden bake creates a bubbly, satisfying main dish perfect for any occasion.

Updated on Mon, 08 Dec 2025 19:55:35 GMT
One-Pot French Onion Mac and Cheese Bake, bubbly with golden breadcrumb topping and melted Gruyère cheese. Save to Pinterest
One-Pot French Onion Mac and Cheese Bake, bubbly with golden breadcrumb topping and melted Gruyère cheese. | nibbro.com

One-Pot French Onion Mac and Cheese Bake is the ultimate comfort food mashup that brings together the rich, caramelized flavors of classic French onion soup with the creamy, cheesy goodness of mac and cheese. This dish is baked to bubbly perfection in a single pot, making it an irresistible, easy-to-make meal that fills your kitchen with the aroma of warm onions and melted Gruyère. Ideal for a cozy family dinner or a special gathering, it combines creamy pasta, deeply savory onions, and a crisp golden breadcrumb topping in every bite.

One-Pot French Onion Mac and Cheese Bake, bubbly with golden breadcrumb topping and melted Gruyère cheese. Save to Pinterest
One-Pot French Onion Mac and Cheese Bake, bubbly with golden breadcrumb topping and melted Gruyère cheese. | nibbro.com

This recipe is perfect for those who crave something warm and satisfying with layers of flavor and a luscious, cheesy finish. Using classic French ingredients like Gruyère and caramelized onions gives this pasta bake an authentic, gourmet touch while the ease of one-pot cooking ensures you spend less time in the kitchen and more time enjoying your meal.

Ingredients

  • Onions: 3 large yellow onions, thinly sliced; 2 tbsp unsalted butter; 1 tbsp olive oil; 1/2 tsp salt; 1/2 tsp sugar
  • Pasta: 400 g (14 oz) elbow macaroni or cavatappi
  • Liquids: 900 ml (4 cups) low-sodium vegetable broth; 250 ml (1 cup) whole milk
  • Cheeses: 200 g (2 cups) Gruyère cheese, shredded; 100 g (1 cup) sharp white cheddar cheese, shredded; 60 g (1/2 cup) Parmesan cheese, grated
  • Seasonings: 2 cloves garlic, minced; 1/2 tsp dried thyme; 1/2 tsp black pepper; salt to taste
  • Topping: 60 g (1 cup) fresh breadcrumbs; 2 tbsp unsalted butter, melted; 2 tbsp parsley, finely chopped (optional)

Instructions

1.
In a large oven-safe pot or Dutch oven, heat butter and olive oil over medium heat. Add sliced onions, salt, and sugar. Cook, stirring frequently, for 20–25 minutes, until the onions are deeply golden and caramelized.
2.
Stir in minced garlic and thyme, cook for 1 minute until fragrant.
3.
Preheat oven to 200°C (400°F).
4.
Add dry pasta directly to the pot with onions. Pour in vegetable broth and milk. Stir well, scraping up any browned bits.
5.
Bring to a simmer, cover, and cook on medium-low for 10–12 minutes, stirring occasionally, until pasta is just al dente and most liquid is absorbed.
6.
Remove from heat. Stir in Gruyère, cheddar, and half the Parmesan cheese until melted and smooth. Taste and adjust salt and pepper.
7.
In a small bowl, combine breadcrumbs with melted butter. Sprinkle evenly over the top of the pasta. Top with remaining Parmesan.
8.
Transfer the pot (uncovered) to the oven. Bake for 10–15 minutes, until golden and bubbling.
9.
Let rest 5 minutes. Garnish with chopped parsley before serving, if desired.

Zusatztipps für die Zubereitung

To ensure perfectly caramelized onions, be patient and stir frequently to prevent burning. Using an oven-safe Dutch oven makes the transfer from stovetop to oven seamless and helps retain all the flavors. Stir the cheese gently to incorporate smoothly, creating a luscious sauce that coats every noodle.

Varianten und Anpassungen

For a richer flavor, replace half of the vegetable broth with beef broth (note: this is not vegetarian). Add sautéed mushrooms or crispy bacon to customize the dish further. While Gruyère offers a signature French onion taste, Swiss cheese or Emmental are excellent alternatives if preferred.

Serviervorschläge

This mac and cheese bake is perfect served straight from the pot with a simple green salad or steamed vegetables on the side. Garnish with freshly chopped parsley for a pop of color and freshness that complements the rich, cheesy pasta.

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| nibbro.com

With tradition and convenience beautifully combined, this One-Pot French Onion Mac and Cheese Bake delights with its sophisticated flavors and effortless preparation. It’s an inviting dish that brings warmth and a touch of elegance to any meal.

Recipe FAQs

How do I achieve perfectly caramelized onions?

Cook sliced onions slowly with butter, olive oil, salt, and sugar over medium heat for 20–25 minutes, stirring frequently until deeply golden and soft.

What types of cheese work best for this dish?

Gruyère provides a nutty flavor, while sharp white cheddar adds tanginess and Parmesan contributes a savory finish. Swiss or Emmental can be used as alternatives.

Can I prepare this dish without an oven-safe pot?

Use a stovetop pot to cook up to the baking step, then transfer to a baking dish for the oven phase to achieve the crispy topping.

What can I add to enhance the flavor?

Try sautéed mushrooms or crispy bacon for extra savory notes. Fresh parsley sprinkled on top adds a bright finish.

How do I know when the pasta is ready before baking?

Cook the pasta in broth and milk until just al dente, typically 10–12 minutes, with most liquid absorbed before adding cheeses and baking.

French Onion Mac Cheese Bake

Creamy mac and cheese meets caramelized onions in a baked, cheesy, and flavorful one-pot dish.

Prep Time
20 minutes
Cook Time
40 minutes
Total Duration
60 minutes
Created by Evan Brooks


Skill Level Medium

Cuisine French-American

Makes 6 Portions

Diet Preferences Meatless

What You'll Need

Onions

01 3 large yellow onions, thinly sliced
02 2 tablespoons unsalted butter
03 1 tablespoon olive oil
04 1/2 teaspoon salt
05 1/2 teaspoon sugar

Pasta

01 14 ounces elbow macaroni or cavatappi

Liquids

01 4 cups low-sodium vegetable broth
02 1 cup whole milk

Cheeses

01 2 cups shredded Gruyère cheese
02 1 cup shredded sharp white cheddar cheese
03 1/2 cup grated Parmesan cheese

Seasonings

01 2 cloves garlic, minced
02 1/2 teaspoon dried thyme
03 1/2 teaspoon black pepper
04 Salt to taste

Topping

01 1 cup fresh breadcrumbs
02 2 tablespoons unsalted butter, melted
03 2 tablespoons finely chopped parsley (optional)

How-To Steps

Step 01

Caramelize Onions: Heat butter and olive oil in a large oven-safe pot over medium heat. Add sliced onions, salt, and sugar. Cook, stirring frequently, for 20 to 25 minutes until onions are deeply golden and caramelized.

Step 02

Add Aromatics: Stir in minced garlic and dried thyme, cooking for 1 minute until fragrant.

Step 03

Preheat Oven: Set the oven temperature to 400°F (200°C).

Step 04

Combine Pasta and Liquids: Add dry pasta to the pot with onions. Pour in vegetable broth and milk. Stir thoroughly, scraping up any browned bits from the bottom.

Step 05

Simmer Pasta: Bring to a simmer, cover, and cook over medium-low heat for 10 to 12 minutes, stirring occasionally, until pasta is just al dente and most liquid has been absorbed.

Step 06

Incorporate Cheeses: Remove from heat. Stir in Gruyère, cheddar, and half of the Parmesan cheese until fully melted and the mixture is smooth. Adjust salt and pepper to taste.

Step 07

Prepare Topping: Combine fresh breadcrumbs with melted butter in a small bowl. Evenly sprinkle the mixture over the pasta, then top with the remaining Parmesan cheese.

Step 08

Bake: Place the pot uncovered in the preheated oven and bake for 10 to 15 minutes until the topping is golden and bubbling.

Step 09

Rest and Garnish: Allow to rest for 5 minutes. Garnish with chopped parsley before serving, if desired.

Tools You'll Need

  • Large oven-safe pot or Dutch oven
  • Sharp knife and cutting board
  • Cheese grater
  • Mixing bowls
  • Wooden spoon

Allergy Info

For allergen concerns, review each food item and check with your healthcare provider.
  • Contains milk (dairy) and wheat (gluten)
  • May contain traces of other allergens depending on cheese and pasta brands

Nutrition Details (per portion)

Nutritional values are for reference and aren't a substitute for professional health guidance.
  • Kcal: 530
  • Fats: 21 g
  • Carbohydrates: 61 g
  • Proteins: 23 g