Cream Cheese Filled Puff Pastry

Preheat oven and baking sheet to 425. Cut pastry sheet in half length-wise. Fold one of the halves in half and make cuts from the folded side to within about 1 inch of the non-folded side. Unfold and set aside. Beat together the cream cheese, sugar, egg (reserving ~1Tbsp.), and vanilla. Place the uncut pastry half on a sheet of aluminum foil and pour the cream cheese mixture down the middle, so that it comes within about half an inch to one inch of the edges of the pastry. You may not use all the mixture. Pour or dollop a line of jam down the middle. Place cut pastry on top, and seal the edges. Mix 1 Tbsp. reserved egg with 1 Tbsp. water and brush over pastry. Sprinkle with coarse sugar, if desired. Take baking sheet out of the oven and carefully transfer foil with pastry to the baking sheet and bake for about 12-15 minutes.