Preheat the oven to 400°F and line 2 large baking sheets with parchment paper and set aside.
Add the raspberries, cornstarch, and granulated sugar to a medium bowl and toss to combine. Set aside until ready to use.
3 cups fresh raspberries, 2 tablespoons cornstarch, 2 tablespoons granulated sugar
Unfold the two puff pastry sheets and use a rolling pin to gently roll them to smooth out the creases, but don’t press hard, it’s okay if some remain.
1 (17.25oz.) package puff pastry
Use a pizza or knife to cut each of the sheets into 4 squares. Transfer the pastries to baking sheets, placing 4 on each. Set aside.
In a large bowl or stand mixer fitted with a paddle attachment, cream together the cream cheese and sugar until smooth.
8 ounces cream cheese, ⅓ cup granulated sugar
Beat in the egg yolk, vanilla, and salt until fully combined.
1 large egg yolk, 1 teaspoon vanilla extract, ¼ teaspoon salt
Use a medium cookie scoop to scoop the cream cheese mixture onto the center of the puff pastries. About 2 tablespoons per pastry. Then spread out the mixture on the pastry.
Beat together the egg and water to create the egg wash and brush on the pastry around the cream cheese mixture.
1 large egg, 1 teaspoon water
Spread the raspberry mixture diagonally from one corner to another on top of the cream cheese mixture. Fold one of the non-raspberry edges over the raspberry mixture and brush with the egg wash. Then fold over the other side and gently pinch together and brush the other side with egg wash.
Bake one baking sheet at a time for 18 to 20 minutes each, placing the other in the fridge while the first one bakes.
Let cool slightly and dust with powdered sugar before enjoying.
Powdered sugar