Preheat the grill to medium high heat, around 400 degrees.
In a bowl, combine the softened butter, Parmesan cheese, garlic powder, salt, and parsley.
Generously spread the butter mixture onto each ear of corn. Wrap them individually in heavy duty aluminum foil, being sure to seal them tightly and twist the ends.
Place the corn on the hot grill and cook for 16 - 20 minutes, turning several times, until the ear of corn feels soft when squeezed with tongs.
Remove from heat and serve immediately with more butter or a sprinkle of Parmesan cheese, if desired.
To roast corn on the cob in the oven: Follow the same recipe instructions (slathering the corn with butter and wrapping in aluminum foil), then pace the corn on a baking sheet in a 400-degree oven. Turn the corn with tongs every few minutes until it is tender, about 15 - 20 minutes.