How potato flakes help a meat pie hold its shape
Ground meat gives off moisture and fat as it cooks. If those juices collect inside a pie, the filling can settle as it cools, leaving a dip beneath the top crust. Potato flakes help by soaking up some of that liquid: they soften, swell, and turn loose juices into a thicker mixture.
A small change to the filling
The flakes also add dry bulk, so the filling is less likely to slump when the meat shrinks during cooking. They work as a practical thickener, much like a sponge mixed into the pie—not as a support that props up the pastry from underneath.
The result is a filling that stays more evenly packed, helping the crust keep its rounded profile instead of sinking over a puddle of cooking juices.
