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Upside Down Onion Tarts

A recipe that’s sure to impress!

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Pastries are one of my greatest weaknesses. Sweet or savory, I’m more than happy to indulge in any treat with layers of buttery dough. I try to limit my trips to the local bakery as those purchases add up fast these days, and puff pastry has been my saving grace for making treats at home! This easy Upside Down Onion Tart recipe utilizes this premade pastry dough for a stunning treat you’ll want to make again and again.

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If you’re not familiar with puff pastry, it’s an item you’ll find in the frozen aisle, typically with the desserts. You’ll want to keep it frozen until the day you want to bake it. At that time, it can be thawed in 6-8 hours in the fridge or at room temperature for about 40 minutes. For the best results, I don’t recommend microwaving it, but in a real pinch it works.

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For these tarts I’ve gone with sweet onions and swiss cheese, but you could really get creative with the customization here. Serve them as a savory breakfast treat or a gorgeous side with a big salad. Your family and friends are sure to be impressed with the presentation and assume you’ve been busy in the kitchen all day long. Give them a try for your next gathering and you’re bound to have a new go-to recipe!

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Makes 12 tarts

10m prep time

15m cook time

Rated 4.6 out of 5
Rated by 5 reviewers
  • 1 (17 oz) box puff pastry, thawed
  • 4 tablespoons olive oil
  • 2 tablespoon balsamic glaze, premade
  • 1-2 medium-sized sweet onions, sliced in rounds
  • 1 teaspoon garlic powder
  • Salt and pepper to taste
  • 12 slices swiss cheese
  • ¼ cup shredded parmesan cheese
  • 1 egg white
  1. Preheat oven to 400 degrees F and line 2 baking sheets with parchment paper.
  2. Slice pastry dough into squares (for my dough I cut each sheet into 6 squares). Set aside.
  3. Make 6 small pools of olive oil on each prepared baking sheet, 12 in total. Add a drizzle of balsamic glaze to each pool.
  4. Place an onion slice on top of each pool, then season with garlic powder, salt, and pepper.
  5. Top each onion with a slice of swiss and then a square of pastry dough, crimping down edges so dough full covers the cheese.
  6. Brush dough with egg white.
  7. Bake tarts for 12-15 minutes or until golden brown.
  8. Allow tarts to cool for at least 5 minutes before flipping for best results. Drizzle additional balsamic glaze on top if desired.

Recipe adapted from

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