How to Make It
Shuck the corn, stripping the husks back but leaving them attached at the stem end; leave the stem on. Holding an ear of corn in one hand, gather the husk together so that it covers the stem and tie it with a piece of butcher's string, forming a sort of handle. Remove the corn silk. Repeat with the remaining ears of corn.
Put the mayonnaise, grated cheese, chile powder and lime wedges in small serving bowls. Have these ingredients ready on the table, along with butter knives for spreading the mayonnaise.
Light a grill. When it is hot, arrange the corn on the grate with the husks hanging over the edge of the grill (this keeps them from burning). Grill the corn until nicely browned on all sides, 2 to 3 minutes per side (8 to 12 minutes in all), turning with tongs.
Transfer the grilled corn to a platter. Tell all your guests to spread mayonnaise on the corn, then, working over a plate or the platter, sprinkle the ears with grated cheese and chile powder. Squeeze lime juice over the grilled corn and enjoy.