To finish the pot pies, whisk the egg to make an egg wash.
Flour the counter and roll out the puff pastry to about 1/8" –inch, checking to make sure you have at least 1 1/2" -inches of overhang. Using either a paring knife or a large ring, cut out the dough, then brush off the excess flour. Puff pastry works best when it is really cold, so each time you cut out a round, place it onto the tray and back into the refrigerator.
To finish assembling, make sure the filling is cool before brushing the top of each ramekin with the egg wash. Drape a piece of dough overtop and squeeze the dough slightly upwards; making sure it is nice and tight around the ramekin. Refrigerate for at least 15 to 20 minutes.
Meanwhile, preheat your oven to 425º degrees Fahrenheit. Just before you bake the pot pies, brush the dough with the egg wash. Vent the tops to let the steam escape. Bake for about 20 to 25 minutes or until the puff pastry is a dark golden brown (and the internal temperature reaches at least 165º degrees Fahrenheit / 74º Celsius). Once done, let the pot pies sit for a few minutes before serving.