01 - Preheat oven to 350°F. Lightly grease a 12-cup mini muffin pan with cooking spray or butter.
02 - Combine flour and salt in a mixing bowl. Cut in cold cubed butter using a pastry blender or fork until mixture resembles coarse crumbs. Add cold water 1 tablespoon at a time, mixing just until dough holds together when pressed.
03 - Roll dough on a lightly floured surface to 1/8-inch thickness. Cut twelve 3-inch circles using a round cookie cutter. Gently press each circle into the wells of the mini muffin tin, pressing up the sides to form cups.
04 - Whisk brown sugar, corn syrup, melted butter, egg, vanilla, and salt in a medium bowl until completely smooth. Fold in chopped pecans until evenly distributed.
05 - Divide filling evenly among the prepared crusts, using about 1 tablespoon per mini pie. The filling should come nearly to the top of each crust.
06 - Bake for 22 to 25 minutes until filling is set and no longer jiggles in the center, and crusts are golden brown.
07 - Let pies cool in the pan for 10 minutes. Carefully loosen edges with a small knife and transfer to a wire rack to cool completely. Serve plain or topped with whipped cream.