All-Purpose Flour (Best Option)
2 tablespoons per 1 tablespoon cornstarchAll-purpose flour thickens by absorbing liquid and swelling during cooking, forming a starch gel that stabilizes the filling. It is less potent than cornstarch, so a higher quantity is needed. The gluten in flour also adds body to the filling, which can be beneficial for the hearty nature of chicken pot pie.
To avoid a pasty or floury taste, it’s important to cook the flour thoroughly in the fat (butter or oil) before adding liquids, essentially making a roux. This step ensures the flour’s starch granules are fully gelatinized and the raw flavor is eliminated.
Compared to cornstarch, flour produces a slightly more opaque and less glossy filling with a thicker, more substantial mouthfeel. This can enhance the rustic appeal of the dish but may lack the silkiness cornstarch imparts.