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These fun little onion, spinach, and cheddar flaky pastries are the perfect fall accoutrement. Flaky puff pastry dough filled with caramelized onions, spinach, and cheese, and then baked to a golden perfection. Equally perfect on a holiday platter, and as they are on a Monday night football tray!

overhead close up photo of Caramelized Onion, Spinach, and Cheddar Flaky Pastries

Happy Monday, happy fall, and welcome to the last full week of September!

Hard to believe that October first is just one week away. Truly feels like we just welcomed in September. This month has been so crazy busy and full of many ups and downs. It’s been a lot, but after spending the weekend organizing the studio space and preparing for the month ahead, I’m feeling a little more on top of things…

I mean, just slightly. Still a little overwhelmed, but getting organized always helps to calm my anxiety a bit. Plus, I’m feeling really excited for all that’s coming in these next few months. So many fun autumn recipes (did you see Friday’s mulled spiced apple cider doughnuts?), new content, and holiday talk, are in the future!

Can’t wait.

overhead photo Caramelized Onion, Spinach, and Cheddar Flaky Pastries before baking on baking sheet

Today I’m sharing such a delicious recipe that’s kind of perfect for all situations. It’s obviously a great appetizer, but these pastries are equally great as a light dinner with a side salad. And yes, the leftovers the next day for lunch are pretty much perfection.

I made these last week. They’re one of the very first recipes I cooked and photographed in the new studio. Not going to lie, it’s been a big adjustment for me cooking and photographing in a new space. I’m not even close to feeling comfortable yet, but after hours and hours working on these, I finally decided I was happy with them.

Caramelized Onion, Spinach, and Cheddar Flaky Pastries on baking sheet after baking

The recipe came out great the first time around. I mean, what’s not to love about caramelized onions, spinach, and cheese all stuffed into flaky pastry dough? It’s beyond good.

The trouble I was having was more with the photos. For those who do any kind of photography you know that lighting is KEY. I only shoot with natural light and while the new studio has so much incredible natural light, it’s also very different from my old works space (aka my house) and it’s taking some serious getting used to.

I love a good moody photo with shadows and all, so finding the right window is proving to be a challenge. I’m sure over time I will find my grove, but right now there’s a bit of a learning curve, so bear with me! I spent hours on these photos and finally came away with some I am happy with and that make the tarts look just as delicious as they taste.

overhead photo of Caramelized Onion, Spinach, and Cheddar Flaky Pastries

Speaking which, let’s talk recipe details.

These are pretty simple to make. You’ll need some pantry staples like onions, spices, frozen spinach and puff pastry.

Start with caramelizing the onions. The onions need to cook low and slow until they’re golden, sweet, and perfect. It’s about a ten minute process, so practice some patience here, and don’t walk too far away from the skillet. Trust me, I’ve done this and come back to black onions. Not good.

Once the onions have caramelized, add the herbs, spices, spinach, and cheeses. I uses a mixed of cheddar and havarti. The cheddar adds a nice sharp flavor, while the havarti adds a buttery creaminess. Both would be delicious on their own, but I love pairing them together for a sharp, buttery, and creamy cheesy flavor.

Stuff the spinach filling in between sheets of puff pastry and then bake. I brushed half of my pastries with everything bagel spice, which is delicious, but also not completely needed. I loved both versions, so use the everything spice if you’d like, these are great with or without!

What you must do however, is drizzle each pastry with honey and then sprinkle with fresh thyme and flaky salt just after they come out of the oven. I know it may seem odd, but trust me here, the honey, thyme, salt combo…game changer.

It’s the best finishing touch.

I’m loving the idea serving these up for some Monday night football snacking or just an easy, but different dinner to break out of the usual chicken and veggie situation that often happens on a Monday night.

You could also save the recipe, and use as your next party appetizer (hello Halloween parties, Friendsgiving, and Thanksgiving I’m looking at you). Better yet, serve these tonight AND at your next gathering!

If you make these caramelized onion, spinach, and cheddar flaky pastries, please be sure to leave a comment and/or give this recipe a rating! Above all, I love hearing from you guys and always do my best to respond to each and every comment. And of course, if you do make this recipe, don’t forget to also tag me on Instagram! Looking through the photos of recipes you all have made is my favorite!