Start by preheating your oven to 350 degrees. Lightly grease your large baking dish with cooking spray.
This prevents the chicken from sticking to the bottom.
Grab your large mixing bowl for the next step. Combine the soup, sour cream, and some melted butter.
Whisk them together until the mixture is very smooth.
Fold your cooked, shredded chicken into the creamy sauce. Add your salt, pepper, and garlic powder now.
Stir it well so the chicken is fully coated.
Pour the chicken mixture into your prepared baking dish. Spread it out evenly using a spoon or spatula.
Ensure it reaches all the corners of the pan.
Crush your crackers into small bits inside a bag. Mix the crumbs with the remaining melted butter.
Sprinkle this buttery layer over the entire casserole top.
Sprinkle the poppy seeds over the cracker crumb layer. Place the dish in the oven for thirty minutes.
Bake until the sauce bubbles and the top glows.