Preheat oven to 400 degrees F. Chop top of garlic bulb off to expose the top of each garlic clove. Drizzle with olive oil, sprinkle with salt and pepper, and wrap in aluminum foil. Roast in oven until garlic cloves are soft, about 45 minutes. Unwrap and let cool.

Heat grill to medium heat. Pull back corn husks and remove silks. Replace husks around the corn, removing outer husks so only a single, non-continuous layer of husks remain.

Grill for 15-20 minutes, turning every 5 minutes, until corn is blackened. Coat corn with butter, garlic, salt, and pepper. Serve immediately.