Prepare the barbecue for direct cooking over medium heat (180° to 230°C).
While the barbecue is preheating, mix the sour cream, mayonnaise, and coriander in a bowl, and season with salt and pepper. Rub the corn with olive oil, salt, and pepper.
Barbecue the corn over direct medium heat, with the lid closed, until browned in spots and tender, 10 to 15 minutes, turning occasionally. Remove from the barbecue.
Barbecue the corn over medium heat, with the lid closed, until browned in spots and tender, 10 to 15 minutes, turning occasionally. Remove from the barbecue.
While the corn is still hot, coat with the coriander cream sauce on all sides. Squeeze fresh lime juice on the corn and sprinkle with the Parmesan cheese.
Just before serving, finish with a light dusting of paprika and cayenne pepper.
