Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the cooked and shredded chicken with cream cheese, garlic powder, onion powder, dried parsley, salt, black pepper, and melted butter.
Unroll the crescent roll dough and flatten each triangle gently with your hands.
Place a generous spoonful of the creamy chicken filling in the center of each triangle.
Fold the dough edges over the filling to create a pocket, sealing the seams tightly.
Brush the tops of the filled Chicken Pillows with a beaten egg wash and sprinkle panko breadcrumbs on top if desired.
Arrange the pillows on the baking sheet and bake for 20-25 minutes or until golden brown.
In a saucepan over medium heat, melt the butter and whisk in flour to create a roux. Gradually add in whole milk and heavy cream while whisking.
Let the sauce simmer for about 5-7 minutes, then stir in grated Parmesan cheese, garlic powder, salt, and black pepper.
Once your Chicken Pillows are golden brown and crispy, drizzle the warm creamy Parmesan sauce over each pillow before serving.