Add chocolate chips and espresso powder to a mixing bowl.
In a small pot, heat the heavy cream over medium high heat. Once it starts steaming, but before boiling, pour it over the bowl of chocolate chips. Let it sit for 5 minutes to allow the hot cream to melt the chocolate chips.
Once the 5 minutes has passed, slowly whisk the mixture together. It will be clumpy at first, but will slowly begin to combine.
In a separate bowl, add the cream cheese and sugar. Use a hand mixer to blend together for about 1 minute, then add the vanilla and combine.
On a parchment covered baking sheet, place the puff pastry sheet on it and cut into 6 pieces.
Use a paring knife to cut a rectangle within each piece of puff pastry about an inch from the edge and not all the way down. Cut just enough so the pastry will rise around the filling when baking.
Whisk the egg and water together to create an egg wash. Brush the edges of the puff pastry.
Fill each center, within the border you created, by spooning in the cream cheese mixture. Place the baking sheet in the freezer for 5 minutes before baking.
Bake for 18-20 minutes in a 400°F preheated oven until golden brown.
Let cool for 5 minutes, then spoon on the ganache.
Top with mini chocolate chips and powdered sugar if desired.
Serve and enjoy!
Notes
Place the baking sheet in the freezer before baking allows the puff pastry to get cold again to ensure a good puff when it bakes.