01 - Preheat the oven to 375°F. Line a baking tray with parchment paper.
02 - In a mixing bowl, combine the cooked chicken, cream cheese, green onions, garlic powder, onion powder, salt, pepper, and parsley. Mix until well blended and all ingredients are evenly distributed.
03 - Unroll the crescent dough and separate into 8 triangles. Spoon an equal portion of the chicken mixture onto the wide end of each triangle.
04 - Roll each triangle up from the wide end toward the point, tucking in the sides to seal the filling inside and form a neat pillow shape.
05 - Place the pillows seam-side down on the prepared baking tray. Brush the tops evenly with melted butter.
06 - Bake for 20 to 22 minutes, or until the pillows are golden brown and cooked through.
07 - While the pillows bake, melt the butter in a saucepan over medium heat. Add the flour and whisk continuously for 1 minute to form a roux.
08 - Gradually whisk in the whole milk, making sure no lumps form. Cook, whisking constantly, until the sauce thickens, about 3 to 4 minutes.
09 - Stir in the grated Parmesan, salt, pepper, and nutmeg until the cheese melts and the sauce is smooth. Remove from heat and fold in the chopped parsley.
10 - Arrange the warm chicken pillows on plates and spoon the creamy Parmesan sauce generously over the top. Serve immediately.