This is a great recipe that is sure to impress at any backyard get-together. Grill corn 20 minutes, rotating a quarter turn 3 times. Mix 1/2 cup mayo with 1.5 cups sour cream, then add 1/8 tsp pepper and 1/4 pepper salt. Gather 1 cup parmesan cheese, 1 lime (quartered), cilantro, and chili powder. These will be your toppings. After the corn is done grilling, coat with the mayo/sour cream mixture on all sides. Then top with squeezed lime, chili powder, cilantro, and cheese. Enjoy these can be a little messy.