Preheat the oven to 375° F.
In a medium saucepan, sauté onion in butter over medium-low heat until tender, about 5 minutes. Then, stir in flour, sage, and a pinch of salt and pepper. Continue to cook for few more minutes.
Next whisk in chicken broth and milk a little at a time, stirring until well blended. The mixture will be thick at first, but will become perfectly smooth and creamy.
Bring to a boil over medium heat and let simmer for a minute.
Finally, add in your turkey, peas, and carrots.
Line a 9″ pie plate with one of the store-bought prepared crusts and fill it up with a delicious turkey filling.
Top your pie with a second crust and pinch the edges together to seal. Cut a few slits to let the steam escape while baking.
Bake your dish for 35-40 minutes or until it’s lightly browned and the filling is warm and bubbly.
Cool for 10 minutes before cutting and serving. Enjoy your delicious Turkey Pot Pie!