01 - Preheat oven to 350°F. Lightly grease a 12-cup mini muffin pan with cooking spray or butter.
02 - In a medium bowl, whisk together flour and salt. Add cold cubed butter and use a pastry cutter or fingers to work it in until mixture resembles coarse crumbs. Sprinkle with cold water, 1 tablespoon at a time, mixing gently until dough just comes together.
03 - Roll dough out on a lightly floured surface to 1/8-inch thickness. Use a 3-inch round cutter to cut 12 circles. Gently press each circle into the wells of the mini muffin tin, pressing up the sides.
04 - In a separate bowl, whisk together brown sugar, corn syrup, melted butter, egg, vanilla, and salt until completely smooth. Stir in chopped pecans until evenly distributed.
05 - Spoon approximately 1 tablespoon of pecan filling into each prepared crust, being careful not to overfill as the filling will expand slightly during baking.
06 - Bake for 22-25 minutes, or until filling is set and crust is golden brown. The centers should still have a slight jiggle but not be liquid.
07 - Let pies cool in the pan for 10 minutes. Carefully run a knife around the edges and remove to a wire rack to cool completely. Serve plain or topped with whipped cream if desired.