My delicious French Onion Mac and Cheese recipe is a grown-up twist on everyone’s favorite childhood dish. I caramelize onions until rich and jammy, then make a homemade cheese sauce with a blend of Gruyère and cheddar before mixing it with macaroni and baking until golden and bubbly. It’s everything I love about French onion soup and mac and cheese combined into one mouthwatering meal!
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Hey guys! Jess here. I’m a proud onion fanatic. It’s my favorite food, seriously. My stepdaughter, Bijou, and I have a game called “Anything or Onions,” where Bijou has me choose between a random delicious food (ex: chocolate) or onions… I choose onions every time. Maybe it’s weird, but onions can be spicy, sweet, crunchy, or velvety smooth, as they are in this French onion mac and cheese recipe! It’s two of my family’s favorite dishes in one, and it’s always a hit at parties and potlucks.
Yes, caramelizing the onions takes time, but as in Amy’s French onion soup recipe, the flavor payoff is SO worth it. Everything else comes together pretty quickly, so it’s totally doable on a weeknight. If you love French onion soup and mac and cheese, I highly encourage you to try this recipe and taste the magic for yourself!
What’s in this French Onion Mac and Cheese Recipe?
Don’t be intimidated by the long ingredients list in this recipe for French onion soup mac and cheese—most of it’s pantry staples and seasonings! Scroll down to the recipe card below for the exact measurements.
- Baguette: French onion soup is usually topped with bread and melted cheese, so I replicate that by topping the macaroni with toasted baguette slices. Slice half a baguette into 12 slices (about 1/2 an inch each).
- Garlic: I like to rub my toasted baguette slices with garlic for extra flavor. This step is optional, but if you’ve got fresh garlic on hand, I recommend it!
- Jumbo Elbow Macaroni: Elbow macaroni is the classic choice for mac and cheese. I went for jumbo-sized, but regular-sized elbows will work, too.
- Butter and Olive Oil: Used to caramelize the onions. I also add a little more butter to the pan to make a roux with the flour to thicken the cheesy sauce.
- Sweet Onions: Be sure to slice your onions nice and thin for even caramelization. I use 4 cups of sliced onions in total.
- Dijon Mustard: Adds the most delicious tang to the cheese sauce.
- Balsamic Vinegar: For deglazing the pan after caramelizing the onions. It helps unstick any browned bits from the bottom of the pan and adds a rich depth of flavor.
- Flour: For thickening the French onion mac and cheese sauce.
- Evaporated Milk and Whole Milk: This combination makes for a creamy, rich sauce that won’t separate or curdle too easily. Be sure to use evaporated milk, NOT condensed milk! Your whole milk should also be at room temperature.
- Aged Cheddar and Gruyère Cheese: Gruyère is a classic choice for French onion soup, while cheddar is often used in mac and cheese. Together, they make a deliciously balanced cheese sauce for this recipe! I like to use high-quality aged cheddar cheese for maximum flavor.
- Seasonings: Salt, a bay leaf, dried thyme, dried parsley, paprika, garlic powder, and onion powder make a delicious French onion soup dry mix, which I use to season the onions before caramelizing.
Tips for Success
- Don’t overcook the macaroni. I only boil the macaroni until al dente, which means it still has a little bite to it. It’ll continue cooking in the oven with the cheese sauce. If it’s cooked too long on the stovetop, it’ll become mushy and lose its texture when it’s baked.
- Shred your own cheese. Go for blocks of Gruyère and cheddar and shred them yourself for the best results. Pre-shredded cheeses often have added anti-caking agents to stop them from clumping in the bag, which can affect the melting and texture of your cheese sauce.
- Take your time while caramelizing the onions. Don’t try to rush this step; it’s crucial to achieving that deep, rich onion flavor. Low and slow is the key here. I let my onions cook for about 30-45 minutes until they’ve turned a deep golden brown color.
- Add the cheese gradually. I know everything smells AMAZING, and you want to get it in the oven so you can serve it. But adding all that cheese into the sauce at once can make it clump together. I recommend adding the cheese in batches, whisking until it’s completely melted and smooth before adding more.
- Don’t bring the sauce to a boil! This can make your cheese sauce grainy and affect the overall texture. I only bring it to a simmer to thicken before adding the cheese.
Serving Suggestions
This French onion soup mac and cheese works great as a main meal or a side dish. I love serving it with a simple green salad dressed in a tangy vinaigrette to balance the rich flavors of the cheesy sauce. But it would also be an amazing dish to bring to a potluck, BBQ, or family gathering. Serve it as a side with baby back ribs, baked chicken breast, or any other protein you love!
Proper Storage
- Fridge. Homemade French onion mac and cheese is best served the day it’s made, but you can store any leftovers in the fridge for 3-4 days. Let them cool completely before storing in an airtight container.
- Freezer. I don’t recommend freezing this recipe if you can help it. The creamy sauce might separate, and the noodles can become mushy once thawed. But if you really want to freeze it, portion out individual servings into freezer-safe airtight containers and freeze for up to 2 months. Let it thaw in the fridge overnight before reheating.
- Reheat. Warm up any leftovers in the microwave or in the oven at 350 degrees F. Cover the baking dish with foil if you’re reheating it in the oven to stop the top from burning and keep the moisture in.
I hope you love this delicious and easy recipe – be sure to give it a review below! Also don’t forget to follow Belly Full on TikTok, Instagram, Facebook, Pinterest, and YouTube!
French Onion Mac and Cheese
This French Onion Mac and Cheese recipe combines two comfort food favorites by adding caramelized onions, seasonings, and Gruyère to classic baked macaroni!
Servings: 12 servings (1 cup per serving)
Ingredients
- 1/2 a baguette cut into 1/2 inch slices (12 slices total)
- 4 cloves garlic , peeled and left whole
- 1 pound dry jumbo elbow macaroni
- 5 tablespoons salted butter , divided + extra for greasing your casserole dish
- 2 tablespoons olive oil
- 4 cups sweet onions , julienned
- 2 teaspoons salt , divided
- 1 bay leaf
- 1/2 teaspoon dried thyme
- 1/2 teaspoon dried parsley
- 1/2 teaspoon paprika
- 1 teaspoon garlic powder
- 1 teaspoon onion powder
- 1 teaspoon Dijon mustard
- 1 tablespoon balsamic vinegar
- 3 tablespoons flour
- 1 can (12 ounce) evaporated milk
- 2 & 1/2 cups whole milk , room temperature
- 7 ounce Gruyère cheese , shredded (about 2 cups)
- 7 ounce high quality aged cheddar cheese , shredded (about 2 cups)*
- 1/4 cup crispy fried onions
Instructions
- Preheat oven to 450 degrees F. Slice half a baguette into 1/2 inch slices and lightly toast in oven for 5 minutes. Remove from oven and rub with 4 garlic cloves. Set aside.
- Put a large pot of salted water on to boil. Once ready, add 1 pound of jumbo elbow macaroni, cooking until barely al dente, about 7-8 minutes. Once your macaroni is cooked to barely al dente, strain and cover with a clean, moist towel (*see note.)
- In a sauté pan, add 2 tablespoons of salted butter and 2 tablespoons olive oil over medium heat.
- Once the butter has melted, add 4 cups of julienned onions and 1 teaspoon salt.
- Turn the heat up to medium-high and toss the onions to fully coat them in the butter. To the onions, add 1 teaspoon salt, 1 bay leaf, 1/2 teaspoon dried thyme, 1/2 teaspoon dried parsley, 1/2 teaspoon paprika, 1 teaspoon garlic powder, 1 teaspoon onion powder, and 1 teaspoon Dijon mustard. Stir to combine.
- Then, stir every 2-3 minutes for about 30-45 minutes total until the onions have fully caramelized, turning a deep golden brown color.
- Then, deglaze the pan with 1 tablespoon of balsamic vinegar, scraping up any delicious crispy bits of onion from the bottom of the pan.
- Turn heat down to medium and add 3 more tablespoons of salted butter to the pan. Once melted, add 1 tablespoon at a time of flour, stirring constantly.
- Pour a 12 ounce can of evaporated milk and 2 & 1/2 cups of room temperature whole milk into the pan and stir to combine. Bring to a simmer, stirring often until it becomes noticeably thicker, about 4-5 minutes. If needed, bump the heat up just a smidge.
- Add 1 cup of shredded Gruyère and 2 cups of shredded cheddar cheese, little by little, stirring to combine and only adding the next cheese until the cup before has fully melted.
- Transfer par-cooked macaroni to a buttered large 3 quart casserole dish (I used a 9×13” casserole dish) and pour the finished cheese sauce over the macaroni, tossing it gently to make sure every piece of macaroni is covered in the cheese sauce.
- Sprinkle the top of your macaroni with 1/4 cup of crispy fried onions.
- Place the toasted baguette slices on top of the macaroni and cheese (each serving will have 1 slice of bread on top.)
- Sprinkle the remaining 1 cup of shredded Gruyère on top of the toasted baguette slices.
- Bake in the oven for 15 minutes until the cheese and toasts on top are golden, bubbly, and dark in spots.
- Let everything cool for 5-10 minutes before serving.
Notes
*I find this trick helps the macaroni stay moist but not wet and saves a little olive oil. If you prefer to toss your macaroni in a little olive oil to avoid it sticking together in large clumps, I still recommend the towel trick.
Nutrition
Serving: 1cup | Calories: 454kcal | Carbohydrates: 46g | Protein: 19g | Fat: 21g | Saturated Fat: 11g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 6g | Trans Fat: 0.2g | Cholesterol: 55mg | Sodium: 789mg | Potassium: 374mg | Fiber: 2g | Sugar: 10g | Vitamin A: 706IU | Vitamin C: 3mg | Calcium: 465mg | Iron: 1mg
