Bring a large stockpot pot of water to a rolling boil.
Add ears of corn to water and boil 10-15 minutes, or until tender.
Drain corn and set aside.
Preheat grill to 450 degrees.
While grill is heating, combine mayonnaise, sour cream, and garlic powder together. Chill in refrigerator.
Grill corn for 3-4 minutes per side or until nicely charred. Remove from grill.
Roll hot corn in mayonnaise mixture and then in finely crumbled cheese.
Sprinkle corn with chili powder, salt and pepper, cilantro, and lime juice. Serve hot.