Why You’ll Love This Recipe
French Onion Soup Mac & Cheese blends the deeply savoury, caramelised flavours of classic French onion soup with the creamy indulgence of baked mac and cheese. The result is a luxurious dish featuring golden caramelised onions, nutty Gruyère, and tender pasta enveloped in a velvety sauce. The crispy cheese topping gives it irresistible texture while the rich onion base adds depth and sophistication. I once tried adding a splash of dry white wine to the onions during caramelisation, and it enhanced the flavour beautifully, giving it an even more authentic French onion soup character. Whether served as a main dish or a standout side, this recipe brings comfort, elegance, and unforgettable flavour to the table.
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French Onion Soup Mac & Cheese: A Comforting Fusion of Two Classics
- Total Time: 45 mins
- Yield: 4 servings
- Diet: Vegetarian
Description
A rich, ultra-comforting mac and cheese infused with deep caramelized onion flavor, inspired by classic French onion soup and finished with melty Gruyère and Parmesan.
Ingredients
- 2 tbsp butter
- 2 tbsp olive oil
- 3 large yellow onions, thinly sliced
- 1 tsp sugar (optional, to aid caramelization)
- 1 tsp salt
- 1/2 tsp black pepper
- 2 cloves garlic, minced
- 1 tbsp fresh thyme (or 1 tsp dried)
- 8 oz elbow macaroni or cavatappi
- 2 cups beef broth
- 1 cup heavy cream
- 1 1/2 cups shredded Gruyère cheese
- 1/2 cup shredded mozzarella cheese
- 1/2 cup grated Parmesan cheese
- 1 tbsp cornstarch (optional, for thicker sauce)
Instructions
- Heat butter and olive oil in a large skillet over medium heat.
- Add sliced onions, salt, pepper, and sugar. Cook 20–25 minutes, stirring occasionally, until deeply caramelized.
- Add garlic and thyme; cook 1 minute until fragrant.
- Pour in beef broth and bring to a gentle simmer.
- Add pasta directly to the skillet, stirring to submerge. Cook 10–12 minutes until pasta is tender and liquid is mostly absorbed.
- Lower heat and stir in heavy cream.
- Add Gruyère, mozzarella, and Parmesan. Stir until melted and creamy.
- If thicker sauce is desired, stir in cornstarch mixed with 1 tbsp water.
- Simmer 1–2 minutes, then serve hot.
Notes
- Caramelize onions slowly for best flavor.
- Gruyère is classic, but Swiss works as a substitute.
- Add toasted breadcrumbs on top for crunch.
- Vegetable broth can replace beef broth if preferred.
- Prep Time: 10 mins
- Cook Time: 35 mins
- Category: Main Dish
- Method: One-Pan / Skillet
- Cuisine: French-American Fusion
Ingredients
(Tip: You can find the complete list of ingredients and their measurements in the recipe card below.)
Elbow macaroni or cavatappi
These pasta shapes hold sauce well and maintain a tender bite even after baking.
Onions
Thinly sliced onions caramelise slowly, developing deep sweetness and rich savoury complexity.
Butter
Used for caramelising the onions and creating a silky base for the cheese sauce.
Olive oil
Helps prevent the butter from burning during the long caramelisation process.
Garlic
Adds aromatic depth, enhancing the savoury flavour of the onions and cheese.
Flour
Forms a roux that thickens the mac and cheese sauce.
Beef broth
Brings authentic French onion soup flavour and boosts savoury richness.
Milk or half-and-half
Creates a creamy, smooth base for the cheese sauce.
Gruyère cheese
A classic choice with nutty, slightly sweet flavour that melts beautifully.
Parmesan cheese
Adds salty, robust flavour that complements the Gruyère.
Thyme
Provides earthy, aromatic notes found in traditional French onion soup.
Salt and pepper
Seasonings that balance the sweetness of the onions and richness of the sauce.
Directions
Start by caramelising the onions: heat butter and olive oil in a skillet over medium heat, then add thinly sliced onions. Cook slowly, stirring often, until deeply golden and fragrant. Add garlic and cook briefly. If desired, deglaze the pan with a splash of beef broth or white wine to lift any browned bits.
Meanwhile, cook the pasta until just shy of al dente, then drain. In a pot, melt butter and whisk in flour to form a roux. Slowly add beef broth and milk, whisking until smooth and thickened. Stir in Gruyère, Parmesan, thyme, salt, and pepper until the sauce becomes velvety. Fold in the caramelised onions and cooked pasta, stirring to coat everything evenly.
Transfer the mixture to a baking dish and top with more Gruyère and Parmesan. Bake until bubbly and golden, forming a crisp, cheesy crust. Allow the dish to cool slightly before serving to help it set.
Equipment Needed :
Must-Have Tools to Get Rolling
Here’s what you’ll want to have on hand:
Silicone Spatula – Durable, heat-resistant silicone spatula perfect for mixing, scraping, and spreading. Gentle on non-stick cookware and easy to clean.
Large pot – You’ll need this to boil the whole cabbage head and soften the leaves.
large bowl –Spacious, durable large bowl ideal for mixing, serving, or food preparation. Made from sturdy material and easy to clean.
Sharp knife – For coring the cabbage and slicing out the thick stem in each leaf. A paring knife works best.
Mixing bowl – A big bowl makes it easier to combine your meat and rice filling evenly.
Cutting board – For prepping cabbage leaves and rolling them like a pro.
9×13-inch baking dish – Ideal size to fit your rolled cabbage leaves snugly and prevent them from unraveling.
knife – A sharp, durable kitchen knife perfect for slicing, chopping, and dicing with ease.
Servings and Timing
Serves 6
Preparation time: 20 minutes
Cooking time: 40–45 minutes
Total time: About 1 hour
Storage/Reheating
Store leftovers in an airtight container for up to three days. Reheat gently in a 175°C (350°F) oven for 10–12 minutes to restore creaminess and crispness. Add a splash of milk if needed. Freezing is possible, but the texture of the onions and sauce may change slightly upon thawing.
Variations and Customizations
Onion & Mushroom Mac
Add sautéed mushrooms alongside the onions for extra umami depth.
White Wine Infusion
Deglaze the onions with white wine for a more authentic French onion flavour.
Cheesy Trio Version
Incorporate mozzarella or fontina for additional melt and creaminess.
Broth-Free Creamy Mac
Replace beef broth with cream for a thicker, richer sauce.
Herb Lovers’ Blend
Use rosemary or sage in addition to thyme for aromatic complexity.
Caramelised Shallot Twist
Replace onions with shallots for a milder, slightly sweeter variation.
Gluten-Free Adaptation
Use gluten-free pasta and substitute the flour with a gluten-free thickener.
Protein-Boosted
Fold in shredded rotisserie chicken for a complete meal.
Crispy Crouton Topping
Add toasted baguette pieces on top for a true French onion soup experience.
Vegetarian Variation
Use vegetable broth instead of beef broth for a meatless version.
FAQs
How long does it take to caramelise onions?
Typically 25–35 minutes; low, slow cooking develops the best flavour.
Can I use a different cheese?
Yes, mozzarella, fontina, or Swiss all work well.
Why did my sauce turn grainy?
Cheese may have been added over high heat; melt gently for best results.
Can I make this ahead?
Yes, assemble and refrigerate before baking, or bake and reheat.
Should I cover it while baking?
No, bake uncovered to achieve a golden crust.
Can I use chicken broth instead of beef broth?
Yes, but beef broth gives the most authentic French onion flavour.
Can I add meat?
Cooked chicken or beef works nicely.
Why is my pasta too soft after baking?
Avoid overcooking the pasta initially.
Can I freeze French Onion Soup Mac & Cheese?
Yes, but texture may soften slightly when reheated.
What sides pair well with this dish?
Green salads, roasted vegetables, or crusty bread.
Conclusion
French Onion Soup Mac & Cheese brings together the best qualities of two beloved comfort dishes—sweet caramelised onions and creamy, cheesy pasta. With its richly layered flavours and gorgeous golden top, it’s perfect for holidays, dinner parties, or a cosy night at home. This indulgent fusion dish is sure to become a new favourite for anyone who loves comforting, flavourful meals.
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