Place yogurt in a small bowl. Stir in lime juice and zest, garlic clove and a small pinch of salt.
Lightly cover husked corn with olive oil and salt and pepper.
Prepare a gas grill for direct cooking over medium heat (350° to 450°F).
Grill corn over direct medium heat (all burners on), with the lid closed as much as possible, until corn is browned in spots and tender, 12 to 15 minutes, turning occasionally.
Remove corn to a plate. Roll corn (or brush) in yogurt sauce. Top each ear with crumbled cheese, a sprinkle of cilantro and a dash of chili powder.
Serve immediately.
Notes
* The cheese is salty so don’t use too much salt in the yogurt mixture. * Yogurt mixture can be made up to two hours in advance. Cover and refrigerate.