First create your jam filling. In a pot add your berries, water, sugar, and simmer until the berry mixture thickens into a jam consistency. Keep mixing throughout this process to prevent sticking or burning. It should take 7-10 minutes.
Next, create your frosting by mixing powdered sugar, cream cheese, butter, and vanilla extract. Mix by hand or with a hand mixer.
Cut your puff pastry dough into rectangles and place both the fillings in the center, staying about an inch away from the center.
Wet the edges of the pastry dough and press a clean sheet of pastry dough on top of the one with filling and press firmly around the edges to close the pastry. You can also grab a fork and make imprints into the edges to help close the pastry. I also recommend poking three sets of holes in each pastry for ventilation.
Bake your pastries at 370 for 20 minutes.
Serve with powdered sugar on top!