Preheat oven to 350° F. Spray a 13"x9" baking dish with cooking spray, lightly.
Gather all of the ingredients together and measure them.
Open a tube of crescent rolls and lay the whole sheet in the bottom of the baking dish. Pinch together the seams and cover the bottom and press the dough slightly up the sides.
Bake the dough for 15-20 minutes, until golden. Remove from oven and set aside.
While crust is baking, heat a large frying pan with high sides on medium-high heat. Add the oil, then add the onion and cook for 5 minutes, until translucent and softened.
Lower the heat to medium. Add the cooked chicken, peas and carrots, potatoes, water, poultry seasoning, garlic powder, onion powder, and pepper. Stir together.
Cover and cook for 5-8 minutes, stirring once, until warmed through. Then stir again and remove from heat.
Add the 2 cans of cream of chicken soup and stir well to combine.
Add the filling to the baking dish and spread evenly over the cooked crust.
Open the other tube of crescent rolls and gently stretch to cover the filling in the pan, pinching together the seams. Make sure the dough presses up against the sides of the baking dish. Cut 4 small slits in the dough with a knife. Brush the dough with milk, you don't need to use it all.
Bake uncovered for 20-30 minutes, until the top crust is golden brown and fully cooked. Serve immediately.