Preheat your oven to 400°F and line two large baking sheets with parchment paper. Mix melted butter, honey, and salt in a small bowl.
Toss asparagus in olive oil in a medium bowl.
On a lightly floured surface, roll out each puff pastry sheet into a 15”x10” rectangle. Cut each into 6 squares, making a total of 12 squares.
Rotate each square to form a diamond shape, then brush with the butter mixture. Place a slice of prosciutto on top, adjusting as needed to fit. Add a few asparagus pieces and a slice of brie. Fold the left side over the top, brush with egg wash, then fold the right side over, brushing the top and sides with more egg wash. Sprinkle with black pepper. Repeat with the remaining puff pastry.
Bake until golden brown and the brie is melted, approximately 15 minutes.
Brush with more of the butter mixture before serving.