What’s not to love about a puff pastry appetizer? And this Caramelized Onion, Mushroom, Apple, & Gruyere Bites recipe pairs that flaky, buttery base with a savory vegetarian topper.

So much to like about this appetizer!

Salty. Sweet. Tart. You get all those notes in this hearty appetizer.

Perfect for any holiday−Thanksgiving, Christmas, New Year’s, Easter−it will knock the socks off your guests with its elevated flavor profile.

Looking for More Appetizer Options?

Check out these appetizer options that are all sure to please:

Six Ingredient Warm Pear Brie Arugula Naan Ready in less than 20 minutes, this recipe makes entertaining so simple and your guests will gobble it up. Better make 2! She’s a stunner, too!

Crostini with Goat Cheese, Prosciutto, and Fig Jam This is my favorite no-fail, quick-prep, go-to appetizer of choice.

Butternut Squash Apple Bruschetta The combination of baked butternut squash and apple paired with creamy ricotta on top of a crostini provides all the textures your mouth didn’t even know it needed.

Sweet Potato Crostini With two topping options, this is a quick two-for-one appetizer. Choose either the salmon or cranberry toppings. Or choose both!

Winter Caprese Salad with Caramelized Delicata Squash Missing the simple and classic Caprese Salad of summer? Here’s a way to transition that same idea into the winter months. It’s simple. It’s deconstructed. And it’s delicious.

Simple to Make | Made to Impress−Caramelized Onion, Mushroom, Apple, and Gruyere Bites

Get the recipe from: Table for Two

While the time commitment on this appetizer might seem a bit daunting−especially during the holidays−you’ll be glad you set aside the time for these savory, salty, sweet bites.

Let’s be honest. The smell of the caramelized onions alone is well worth the effort. They’ll fill your kitchen with an alluring sweet and buttery aroma.

And the reward of the flaky pastry crust under that caramelized goodness will have you making these even if you aren’t hosting a holiday meal.

So, grab that sauce pan and start caramelizing those onions!

Caramelized Onion, Mushroom, Apple, and Gruyere Bites ingredients minus the apples. I forgot to slide them into the frame! Oops!

Seven things to know about the Caramelized Onion, Mushroom, Apple, and Gruyere Bites recipe:

  • This recipe takes some time, but it’s worth it. Caramelizing the onions is a necessary but somewhat long process. And you don’t want to rush it. Cooking the mushrooms and apples also takes a bit of time. Then you need to fill and bake the pastry. All necessary steps for the final, amazing result.
  • You can prep the filling up to 2 days in advance. If you’re making this for the holidays, that’s a game-changer. Get your prep work done and then you just need to dollop the filling on the pastry squares and bake them.
  • My onions only took about 15-20 minutes to caramelize. Yes, I just said not to rush the process and now I’m telling you my onions caramelized faster than stated in the recipe (30 minutes). That’s just how caramelization goes sometimes. I halved the recipe so I had fewer onions to caramelize which is likely why my timeframe was shorter. When it comes to caramelizing onions, the onions will speak to you. Let them bask in the oil and slowly caramelize to bring out all their sweet goodness. Don’t try to speed up this process. They’re caramelized when they’re caramelized.
Caramelizing onions takes time, but the flavor reward is worth it!
  • I added a bit more oil before I sautéd the mushrooms. My pan was fairly dry after I caramelized the onions, so I needed a bit more oil so the mushrooms wouldn’t burn. If you need more oil, add it. If you don’t, don’t. It’s as simple as that.
Caramelized Onion, Mushroom, Apple, and Gruyere filling.
  • I used the natural seams on the puff pastry as my cutting guideline. One sheet of puff pastry yielded 12 squares. Easy peasy.
  • Load up that filling! I put a significant amount of filling on my puff pastry squares and wasn’t very neat about making sure it was centered with clean edges. That’s the beauty of puff pastry−it’s going to puff up and nestle your filling in its flaky goodness.
Puff pastry squares before and after filling!
  • My pastry only took 17 minutes to bake. Because I was only making half a recipe, I only had one sheet pan of pastry to bake which explains why it baked faster than the 25 minutes noted in the recipe. Set a timer for 12-15 minutes and check the pastry’s progress. Like the caramelized onions, the pastry will tell you when it’s done. You’re looking for golden brown, crispy goodness throughout (bottom and top).

Next time you’re looking to make an impressive appetizer, try these Caramelized Onion, Mushroom, Apple, and Gruyere Bites. Most delicious!

Caramelized Onion, Mushroom, Apple, and Gruyere Bites