Tender mushrooms and balsamic caramelized onions take this luxurious mushroom mac ‘n’ cheese to another level! – the best way to fancy up mac ‘n’ cheese night.

You’re about to meet the most hard-core comfort food EVER today!
We love a good fancified mac around here and this caramelized onion + mushroom stuffed version just ticks all the boxes.
And handily enough, it’s easy enough that you can pull it off on any regular ol’ weeknight! Music to everyone’s ears.

So it turned fall here like overnight, guys. Not even kidding the amount of soups, casseroles, and basically anything HOT that we’re making around here these days.
Mac ‘n’ cheese is totally a year-round kinda comfort food deal but even more so right now.
Let’s pump up the flavors in a childhood classic today with incredible ingredients like caramelized onions, mushrooms, and balsamic!
This Caramelized Onion Mushroom Mac ‘n’ Cheese features…
- Deeply flavorful caramelized onions
- Balsamic sauteed mushrooms
- A rich cheese sauce made from rich cheddar and Parmesan
- Classic elbow pasta, but feel free to use whatever pasta shape you like!

Making the Caramelized Onion Mushroom Mac ‘n’ Cheese
(scroll down to the bottom of post for the full recipe)
Ingredients You Will Need
- Sweet onion
- Mushrooms
- Olive oil
- Unsalted butter
- Garlic
- Balsamic vinegar
- All-purpose flour
- Milk
- Half and half cream
- Parsley
- Cheddar cheese
- Parmesan cheese
- Pasta
How to Caramelize Onions
You will need 1 medium sweet Vidalia onion to make caramelized onions. Slice the onion into thin strips and it’s ready for cooking!
The trick with caramelizing is a low ‘n’ slow process and you’re going to want to cook the onion in a little butter + olive oil over medium heat about 20 minutes. Stir the onions occasionally until they are a deep caramelized brown.
That’s it! Caramelized onions are such a flavor boost to many dishes and a great thing to make ahead of time to store in the fridge for reheating later.

Tips for Perfect Mac ‘n’ Cheese
- Make a roux – this is equal parts butter and flour and it is the base to your sauce. Cook the roux over medium heat, whisking constantly until a light golden brown.
- Slowly drizzle in milk + cream – use a whisk to evenly incorporate the liquids into the roux and avoid lumps.
- Cook sauce over medium heat – once all the liquids have been added, cook the sauce over medium heat and stir often to avoid burning. The sauce is done when it’s bubbly and can coat the back of a spoon.
- Fold cheeses in offheat – this will help prevent the cheese from burning. Once the sauce is thickened, remove from heat and whisk in cheeses until melted.
- Bake mac ‘n’ cheese – an extra step but so worth it! This is how you get those lovely crispy, browned edges everyone loves.
Recipe Variations
This macaroni is so easy to change up based on your preferences! Try these ideas out…
- Change up the cheese – try a combo of shredded gruyere + asiago or monetary jack + sharp cheddar.
- Try another veggie – if you’re not a fan of mushrooms, try sauteed zucchini, sweet pepper, or peas.
- Add meat – cooked chicken, sausage, or bacon would be a great meaty addition.

This mac is just one for the record books, y’all. The caramelized onions, balsamic, and mushrooms add the most incredible savory flavors to the rich macaroni base. It just can’t be beat.
Meet your new comfort food addiction. It’s this winner right here!
Save this recipe using the ‘save to recipe box’ button below. If you make it, please let us know! Leave a comment + star rating below, or take a photo and tag it on Instagram with #wholeandheavenlyoven.

Watch this mac ‘n’ cheese made step-by-step on Google web stories!
Try these other mac ‘n’ cheese favorites next time!
- Roasted Red Pepper Sausage Skillet Mac ‘n’ Cheese
- Baked Pumpkin Roasted Red Pepper Mac ‘n’ Cheese
- Chipotle Bacon Butternut Squash Mac ‘n’ Cheese
Balsamic Caramelized Onion Mushroom Mac ‘n’ Cheese
This recipe may included paid links. As an Amazon Associate, I earn a commission from qualifying purchases.
Ingredients
- 1 tablespoon olive oil
- 1 tablespoon plus 1/4 cup unsalted butter, divided
- 1 medium sweet onion, thinly sliced
- 1-1/2 cups thinly sliced button mushrooms
- 2 cloves garlic, minced
- 1/4 cup balsamic vinegar
- 1/4 cup all-purpose flour
- 1/2 cup half and half cream
- 1-1/2 cups milk
- 1-1/2 cups shredded cheddar cheese
- 1/3 cup grated Parmesan cheese
- 1 lb elbow pasta, cooked according to package instructions
- Salt and pepper to taste
- Fresh minced parsley for topping, optional
Instructions
- Preheat oven to 375F. In a large oven-safe skillet over medium heat, melt olive oil and 1 tablespoon butter until pan is shimmery. Add onions and let cook, stirring occasionally until onions are a deep caramelized color, about 20 minutes.
- Add mushrooms to pan and saute an additional 3-4 minutes or until mushrooms are softened. Add garlic and balsamic and saute 1 minute until fragrant. Scrape onion/mushroom mixture into a bowl and set aside.
- In same skillet over medium heat, melt remaining 1/4 cup butter. Whisk in flour until completely smooth and let cook 1 minute until golden brown. Slowly whisk in half and half and milk until mixture is smooth. Bring to a simmer over medium heat until sauce is bubbly and thickened.
- Remove sauce from heat and whisk in cheeses until melted. Add cooked pasta and onion/mushroom mixture and stir until evenly combined. Season with salt and pepper to taste.
- Bake macaroni in oven-safe skillet or in a greased 9×13 baking dish at 375F 15-20 minutes or until bubbly and golden brown. Top with parsley if desired. Serve warm and enjoy!
For a step-by-step guide to making this recipe, check out the video!
Notes
Nutrition
This post was updated with new photos and recipe notes on 7/13/22.
Jessica says
Hi Sarah,
Just looking at the pictures make me crave for this Balsamic Caramelized Onion Mac n Cheese!! And yes, the more cheese the merrier! 😉
Nicole Bogle says
Great! I added a 1/2 cup of smoked cheddar and chicken and it turned out great!
Luisa says
This recipe just amped up my Mac n cheese nights! This was so good that my mother went back for seconds. And she’s the type of person that will never admit my cooking is good ? I’m saving this recipe!
Sarah says
Awww I’m so happy to hear that, Luisa! Glad you and your family enjoyed. 🙂
Katy says
Great inspiration, loved the caramelized onion and mushroom filling for the best comfort dish ever!
Sarah says
Glad you love it, Katy! 🙂
Kim says
Sarah, I love a classic Mac and Cheese, but my goodness does your version sound amazing. The combination of ingredients makes my mouth water. It takes this dish to a whole new level. The perfect indulgence.
Sarah says
It’s definitely a keeper recipe! Let me know if you try it!
G says
Thank you for the recipe. I made it with the following changes, which worked well for me.
Used 2 tbs of balsamic vinegar and found it still very strong.
Sautéed the mushrooms separately until their water cooked off, then combined with the caramelized onions.
Cooked the pasta under el dente so that it finished cooking in the oven and wasn’t mushy.
Sarah says
Thanks for sharing your adjustments! 🙂
Dorota says
This was amazing!!!!! We added some crumbled up bacon on top. Also any tips on reheating this the next day??
Sarah says
Hi Dorota – so glad to hear this mac n cheese was a hit! For reheating, we recommend heating individual servings in the microwave 1-2 minutes on high, stirring once halfway through.
Jackie Dippolt says
Thank you Sarah for another terrific recipe. I’m definitely trying this out this weekend.
Sarah says
Happy to hear that, Jackie! LMK how it turns out!
Emily Gann says
So good, so quick and easy! We also made ours with an espresso balsamic vinegar and it was absolutely *chef’s kiss*
Sarah says
Emily, I’m thrilled to hear that! Thanks for reporting back. 🙂
Sarah says
Just yum!!!! Creamy and delicious… will be making this again!!!
The recipe says it serves 6, do I doubled the recipe for a family party. I had SO MUCH of this Mac & cheese!
Sarah says
That’s amazing! The more mac and cheese the better in my book. 🙂 Thanks for taking the time to report back, Sarah!