How should you prepare baked shells for cream pies before baking?

To prepare baked shells for cream pies before baking, piercing the dough with a fork all over the bottom is essential for preventing the formation of air bubbles during the baking process. This technique, often referred to as "docking," allows steam to escape and helps maintain the integrity of the shell's shape. When the dough is baked, the moisture can create pockets of steam if the dough isn't docked properly, leading to a puffed-up and uneven surface that could negatively affect the appearance and texture of the pie once filled.

Using this method ensures that the baked shell is flat and ready to hold the cream filling without any unwanted bubbles or distortions in the structure. Other techniques, such as brushing with an egg wash or dusting with flour, serve different purposes and do not address the specific issue of steam release within the crust. Additionally, cutting slits in the dough might compromise the shell by allowing moisture to escape in a way that could dry it out or alter its texture unfavorably. Therefore, the accurate preparation method for maintaining the quality of baked shells for cream pies is to pierce the dough with a fork all over the bottom.