Preheat your oven to 400°F and line a baking sheet with parchment paper. While the oven heats, prepare your workspace by having all ingredients ready and measured. I recommend thawing your puff pastry according to package directions well before you start—usually 30-40 minutes at room temperature—so it's pliable but still cold when you begin rolling.
Combine the cooked shredded turkey, prepared stuffing, and cranberry sauce in a bowl and mix thoroughly until well combined. The cranberry sauce acts as both a flavor element and a binder, helping the filling hold together. Make sure the mixture is evenly distributed—you want every bite to have turkey, stuffing, and cranberry sauce.
In a small bowl, whisk together the egg and milk until smooth and well combined. This egg wash will seal the pastry edges and give the rolls their signature golden-brown finish. Set aside until needed.
On a lightly floured surface, roll out the thawed puff pastry to approximately 16 x 9 inches, then cut it in half to create two rectangles. Place about 2 tablespoons of the turkey filling mixture from Step 2 along one long edge of each pastry rectangle, leaving a small border. Brush the opposite long edge with the egg wash from Step 3 to help seal the roll. Carefully roll the pastry over the filling toward the egg-washed edge, creating a tight spiral. I find it helpful to use the parchment paper as a guide to roll evenly and keep the pastry from sticking.
Transfer both rolls seam-side down to your prepared baking sheet. Brush the entire top surface of each roll with the remaining egg wash for an even golden finish. Using a sharp knife, make 3 diagonal cuts about 1/4-inch deep across the top of each roll—this not only helps them cook evenly but also makes them more visually appealing.
Bake the rolls in your preheated 400°F oven for 25-30 minutes, until the pastry is puffed and deeply golden brown. The puff pastry should be crispy on the outside while the filling stays warm inside. Remove from the oven and let cool for a few minutes before serving—this helps the pastry set slightly and makes them easier to handle.