Preheat the oven to 400°F. Line a baking sheet with parchment paper. Thaw pastry per package instructions.
Remove the brie from the wrapping. Use the edge of a sharp knife, scrape the rind from the cheese. If you don't mind the rind, simply leave it on the cheese and skip this step.
Carefully cut the brie in two equal halves.
Using a floured rolling pin, roll out the thawed puff pastry on a lightly floured surface. Shape roughly into a 14 inch square. It doesn't have to be perfect.
Trim the corners, shaping the pastry into a large circle. Leaving at least a 3 inch circumference around the cheese to cover it entirely.
Place the bottom half of the brie into the center of the pastry.
Sprinkle the brown sugar and nuts on top. Dot with butter, then brush the edge with the beaten egg wash. Place the remaining half on top.
Fold the edges of the dough over the cheese pressing firmly. Brush the bottom with egg wash, then flip over so, the smooth side will be on top.
Place onto the baking sheet, and smooth the sides with your hands. Brush top and sides with egg wash. You may garnish the top with cut outs from the trimmed edges, if desired.
Bake for 20 minutes or until golden. Let stand on sheet for 20 minutes.
Cut into wedges and serve with your choice of crackers, apple or pear slices.