In a small bowl, combine pecans, sugar, and salt, using your fingertips to thoroughly mix; set aside. Line a baking sheet with a nonstick baking mat or parchment paper; set aside.
Lightly dust work surface with flour. Place puff pastry on the work surface and roll until it is about 1/8 inch thick. Using a pastry wheel or a sharp knife, cut the puff pastry into a 20-inch square.
Transfer to prepared baking sheet and place Brie in the center of the puff pastry. Top the Brie with pecan mixture, spreading to within 1/2 inch of the edge of the cheese. Be sure to remove any sugar or nuts from the puff pastry, as they may cause holes to form during baking. Bring the corners of puff pastry up and over the cheese and tie with kitchen twine to secure.
Transfer to refrigerator and chill for at least 30 minutes and up to overnight.
Preheat oven to 400 degrees. In a small bowl, combine egg yolk and cream to make an egg wash. Brush the wrapped Brie evenly with the egg wash and bake until golden brown and puffed, about 20 minutes. Reduce oven temperature to 350 degrees and bake until dark golden brown, about 40 minutes more. Let cool at least 45 minutes before serving along with fruits and bread.