Heat the oven to 375°F. Lightly coat a 9x13-inch baking dish with grease or nonstick spray.
Open the crescent dough and separate it into 8 triangles.
Add a small portion of chicken and a little cheddar cheese to the wider end of each triangle. Roll each one up toward the pointed end, keeping the filling tucked inside.
Arrange the filled crescents in the prepared baking dish with the seams facing down.
In a bowl, stir together the cream of chicken soup, milk, garlic powder, onion powder, and black pepper until the mixture is smooth.
Pour the sauce over the crescent rolls, covering them as evenly as possible.
Scatter the rest of the cheddar cheese across the top.
Bake for 25 to 30 minutes, until the crescents turn golden and the sauce bubbles around the edges.
Let the dish rest for about 5 minutes before serving so the sauce can thicken slightly. Sprinkle with parsley if desired.