Par-bake or pre-bake the pie dough in order to achieve a well-cooked flakey pie shell. Line the pie dough with pie weight (like dried beans or rice) to prevent it from forming air bubbles or air pockets in the oven.  The pie crust will be not fully cooked at this point. It will finish cooking with the pecan filling the second time around in the oven. Par-baking ensures that the bottom of the pie crust will not be soggy. It also gives you the chance to re-work the pie crust crimping should it shrink during par-baking.