Puff Pastry Palmiers stuffed with caramelized onions and creamy blue cheese. An easy and elegant appetizer that is sure to be a hit at your next party!
Thaw puff pastry dough according to instructions and preheat oven to 375 degrees F.
Slice onions into thin slices (but don’t chop). Add to a medium pot with butter, brown sugar, vinegar, and a pinch of salt. Set over medium heat and cook until onions start to caramelize. Stir regularly to promote even browning. Cook for 20-25 minutes until onions are lightly browned.
When you’re ready to make palmiers, roll out one sheet of puff pastry on a lightly floured surface. Sprinkle with crumbled blue cheese and spread over half of the caramelized onions.
Roll puff pastry edges in where they meet at the center.
Slice puff pastry log into 12 even pieces and transfer each palmier onto a baking sheet lined with parchment paper. Brush them with egg wash.
Bake palmiers at 375 degrees F. for 15-16 minutes until they are nicely browned.
Let cool briefly before serving. These keep fine at room temperature for a few hours if you need to make them in advance. Store leftovers in an airtight container.