Preheat oven to 350F.  Place brie in freezer for about 1/2 hour prior to assembling to prevent oozing while baking.  Roll 1/4 sheet of puff pastry to even thickness of about 1/8″.  Place brie in center of pastry.  Top with raspberry preserves and then slivered almonds.  Bring corners of puff pastry together and twist to form a knot.  Brush lightly with beaten egg and place on a sheet pan.  Bake for about 20 minutes or until pastry is golden and slightly puffed.  Served immediately with Dijon mustard if desired.