Try this Chicken Pot Pie recipe
Why chill the butter and shortening until rigid before pulsing them into the flour? Fat pieces must remain solid when introduced to the oven heat so they melt and leave behind pockets of steam, resulting in distinct, flaky layers. When adding the very cold water through the food processor tube, stop the machine the exact second the dough begins to clump into a cohesive mass to prevent gluten overdevelopment that yields tough pastry. Keeping the dough wrapped in the refrigerator for at least an hour relaxes those gluten strands and solidifies the fat distribution before rolling.
Building a stable sauce requires cooking the raw flour in the rendered bacon fat and butter mixture until the starch granules expand and lose their starchy taste, which typically takes a minute or two of constant stirring. Substituting low-fat milk for heavy cream fundamentally changes the viscosity of the filling, as higher-fat dairy resists curdling when simmered and provides the necessary mouthfeel to coat the vegetables and cooked chicken. Dry sherry contributes an essential hit of acidity and savory depth that regular cooking sherry—which often contains added salt and preservatives—cannot replicate accurately without throwing off the measured salt content.
Placing the pie directly onto a preheated baking sheet positioned on the bottom third rack of a 400-degree oven guarantees direct bottom-heat transfer, preventing a soggy bottom crust while the top browns. Brushing the rolled pastry with an egg wash made from a whole egg whisked with a tablespoon of milk promotes the Maillard reaction, turning the exterior a deep, glossy golden brown. Allowing the baked pie to rest undisturbed for twenty minutes lets the boiling-hot sauce cool enough to set properly so the interior slices cleanly instead of running across the plate.