Preheat oven to 400 degrees
In a medium-sized saucepan, heat cherries and sugar on medium-low heat until the cherries start releasing their juices. Mash them down very slightly and heat some more until there is a lot of liquid. Whisk corn starch and water together in a small bowl and stir into cherry mixture. Bring to a very gentle boil, continuously stirring, until the mixture thickens enough to coat the back of a spoon. Remove from heat and allow to cool completely.
In a small bowl, beat together cream cheese, butter, sour cream and vanilla until smooth. Add granulated sugar and powdered sugar and beat until completely incorporated. Set aside.
Unroll refrigerated Puff Pastry Dough on enclosed parchment paper and place on a large baking sheet. Cut 16, 3-4” stars into the dough and remove the scraps. If you have a small star, I like to cut out little stars with the extra dough and bake them to prevent waste! Spoon 1 tablespoon of the cream cheese mixture in the center of each star, and top with 1 tablespoon of cherry preserves.
Rub the edges of the star with egg wash and place a second star on top. Crimp the edges with a fork. Some filling may squish out. Cut two tiny slits in the top for vent holes, brush the tops with some egg wash and sprinkle with some sugar.
Bake for 15-20 minutes or until tops are golden.