Preheat oven to 350°F. Lightly spray a 13"x9" baking dish with cooking spray.

Prep Bottom Crust: Open one tube of crescent rolls and lay the whole sheet in the bottom of the dish. Pinch the seams and press the dough slightly up the sides.

Bake Crust: Bake the bottom dough for 15-20 minutes, until golden. Remove from oven and set aside.

Sauté Aromatics: While the crust is baking, heat the oil in a large frying pan over medium-high heat. Add the diced onion and cook for 5 minutes until translucent and softened.

Cook Filling Base: Lower the heat to medium. Add the cooked chicken, peas and carrots, potatoes, chicken broth, poultry seasoning, garlic powder, onion powder, and pepper. Stir together.

Simmer: Cover and cook for 5-8 minutes, stirring once, until warmed through. Remove from heat.

Finish Filling: Add the 2 cans of cream of chicken soup and stir well to combine until smooth.

Assemble Casserole: Add the completed filling mixture to the baking dish and spread evenly over the cooked bottom crust.

Prep Top Crust: Open the second tube of crescent rolls and gently stretch the sheet to cover the filling. Pinch together the seams and press the dough up against the sides of the dish.

Prepare for Bake: Cut 4 small slits in the top dough with a knife. Brush the top dough lightly with the whole milk.

Final Bake: Bake uncovered for 20-30 minutes, until the top crust is golden brown and fully cooked.

Serve: Serve immediately while hot.