In a food processor, combine all-purpose flour, granulated sugar, and kosher salt; pulse briefly to mix. Add chilled butter and cold water, pulsating until a rough dough forms. Knead gently on a floured surface, wrap in plastic, and refrigerate for at least 10 minutes.

Heat extra-virgin olive oil in a large pot over medium heat. Add diced onion, chopped celery, and diced potato, sauté for about 6 minutes. Stir in turkey, cook for 6-8 minutes until browned; season with pepper and salt, add flour to thicken.

Pour in chicken stock, stirring continuously until thickened, about 4 minutes. Remove from heat; fold in cheese, cranberry sauce, and chives.

Preheat oven to 400ºF (200ºC). Roll out dough to about ¼ inch thick. Cut into 4-inch squares and press into muffin tin cups. Fill them with the turkey mixture, cover with another square of dough, sealing edges tightly.

Brush tops with beaten egg and bake for 20-25 minutes until golden brown. Allow to cool slightly before serving warm or at room temperature.