Par boil potatoes for 5 minutes, then drain; the grill will finish cooking them. Season chicken with spices, then sear only in skillet with 1 tbsp. oil. Remove skillet from heat, stir in flour to coat chicken, then add milk and return to medium heat just to thicken. Combine all vegetables into chicken mixture, then set aside to cool.
For topping combine everything but the cheese and mix to a crumbly texture, then add cheese and set aside.
Do not grease pan! Place the pie crust in the pan and press outward and upward from the bottom center. Press top edges to the pan to form an edge, then fill with cooled chicken mixture. Cover with topping mix.