Preheat oven to 375°F. Line a baking sheet with parchment paper.
In a bowl, toss asparagus with olive oil, salt, and pepper.
On a floured surface, roll out puff pastry and cut into 8 equal squares.
Place a slice of brie in the center of each square, then top with a few asparagus spears. Fold two opposite corners of the pastry over the filling and press gently to seal.
Place pastries on the prepared baking sheet and brush each with the beaten egg.
Bake for 20–25 minutes, until the pastry is puffed and golden.
While the pastries bake, combine honey, butter, and thyme in a small saucepan over low heat until melted and fragrant.
Drizzle warm thyme honey over baked pastries and sprinkle with crushed red pepper flakes. Serve warm and enjoy!