After you have husked your corn, lay out a large piece of tin foil, I made 2 packages with 4 in each package. Butter the top of each piece of corn, sprinkle with basil, salt and pepper to taste, and 1/2 the rosemary. Do the same for the other 4 corn on a separate piece of tinfoil. Once done, fold up and double wrap them both. Place on the BBQ and grill for about 10-15 minutes depending on how hot the grill is ours was at 350. and after that I turned them over and cooked another 10 minutes.
Note: you can use dried herbs if you don't have fresh