Preheat the oven to 375°F (190°C). If your mini muffin pan is not non-stick, grease it with baking spray.

Next, roll the pie dough until it's about 1/16-inch thick. Using a 2 1/2-inch circle cookie cutter, cut as many circles out of the dough as you can. Re-roll the dough as needed until you have about 36 pie dough circles. Don't let the pie dough warm up too much, or it will stick and come out dense.

Press the pie dough circles into the cups of the mini muffin tin. Make sure to press the dough flat into the sides and bottoms of the mini muffin cups. You want plenty of room for the filling! I use a dough tamper to do this, but a muddler or teaspoon will work too. Refrigerate the pie doughs while you make the filling.

Add the egg, brown sugar, and white sugar to a large mixing bowl. Whisk the mixture until it's thickened and pale, about 2-3 minutes.

Add the pumpkin, vanilla extract, pumpkin pie spice, cinnamon, cardamom, and salt. Stir just until the filling is smooth. Then, while whisking constantly, add the half-and-half. Mix the filling just until it's combined.

Using a scoop, evenly fill the unbaked pie crusts with pumpkin custard all the way to the top (about 1-1 1/4 tablespoons per pie dough cup).

Bake the mini pies for 18-20 minutes, just until the filling is set and the crust is golden-brown. If the filling is still a bit runny, bake the pies for another 1-2 minutes.

Let the pies cool in the pan for about 5-10 minutes. Use a spoon or butter knife to gently pop the pies out of the pan. Transfer the mini pies to a wire rack to cool completely. Then, refrigerate for 2-3 hours until the custard is completely set.

Right before serving, top each pie with whipped cream. Sprinkle the tops with extra pumpkin pie spice, if desired. Enjoy!