I start by preheating my oven to 400°F and lining a baking sheet with parchment paper. While that heats up, I lightly flour my counter and roll out the thawed puff pastry sheet just enough to smooth out any fold lines. This little step keeps the pastry from cracking later.
In a small skillet, I melt the butter over medium heat, then add the pear slices, brown sugar, cinnamon, and vanilla. I let them cook for about 5-7 minutes, stirring occasionally, until the pears turn soft and golden. This is honestly my favorite part. The smell alone is worth it.
I lay the puff pastry sheet on my prepared baking sheet and score a border about half an inch from the edge, without cutting all the way through. Inside that border, I layer the brie pieces first, then top them with the caramelized pears.
Once everything is layered, I sprinkle the chopped pecans over the top and brush the exposed pastry edges with the beaten egg. This egg wash is what gives the crust that beautiful golden-brown shine once baked.
I slide the tray into the oven and bake for 20-25 minutes, until the pastry has puffed up and turned a deep golden color and the brie is melted and bubbly. I keep an eye on it after the 18-minute mark since ovens can vary.
I always let it rest for about 5 minutes before slicing. This helps the brie set just slightly so it doesn't run everywhere the moment you cut into it. A light drizzle of honey right before serving makes it taste like it came from a bakery.