Add the shortening to the bowl and using two forks or a pastry cutter work the shortening into your flour mixture until the dough resembles small crumbs. Stir in 1 tablespoon at a time of the ice water. Continue adding the ice water and stirring until the dough begins to pull away from the sides of the bowl and forms a ball. The dough should be sticky, but firm. If it is dry, you need to add more water.
Remove the dough ball from the bowl and shape it into a flat disc. Wrap it in plastic wrap and place in the refrigerator to chill while you prepare the pecan pie filling.
For the Pecan Pie Filling:
In a medium mixing bowl, beat in eggs, vanilla, corn syrup and both sugars until thoroughly blended.
Stir in pecans. Set aside.
For the Tarts:
Preheat the oven to 350°F.
On a lightly floured surface, roll out the dough until it is about ¼ inch thick.
Using a small biscuit cutter, cut out circles.
Lightly spray the muffin tin with non-stick cooking spray.
Add the dough circles and push to cover the sides of each hole.
Add 1 ½ tablespoons of the pecan pie filling to each tart.
Bake for 25 minutes or until lightly browned.
Remove the tray from the oven and allow the tarts to cool in the pan.
Use a butter knife to gently remove the tarts from the muffin pan.
Notes
The circles of dough would be about 2.5" wide to fit in a traditional muffin tin that is 2x1 ¼". Use a pastry tart tamper to help you push the pie dough into the muffin pan.