Set the oven to 400°F (200°C) and lightly butter or spray a muffin tin. Roll the chilled pie dough flat and cut circles a bit larger than the muffin wells, using whatever round cutter you have on hand. Press the crust into the cups and let the edges fold naturally; those little rustic folds give each mini pie a homemade charm.
Place the pumpkin puree in a medium bowl, then pour in the condensed milk. Add the eggs along with the extra yolk, followed by the cinnamon, ginger, nutmeg, and a light touch of salt. Whisk everything together until the batter turns silky and evenly mixed. Be gentle, you want a silky filling, not a frothy one.
Spoon the filling into each prepared crust, filling just below the top to leave room for a gentle rise.
Bake at 400°F for 10 minutes to set the crust and start cooking the filling, then reduce the oven to 325°F (160°C) and bake for another 10 minutes. Keep an eye on the crust edges, if they start browning too fast, cover them loosely with foil.
Once baked, transfer the mini pies to a cooling rack for at least 10 minutes to allow the filling to firm up. Admire the warm, golden edges for a moment, then treat yourself.