In a medium bowl, combine butter, cilantro, garlic, lime zest, chili powder and paprika; season with salt and pepper, to taste. Set aside.
Preheat grill to medium heat. Peel back outer husks, leaving them attached at the base of the ear; do not remove inner husks. Remove and discard silks; rinse corn and pat dry using paper towels.
Brush corn with canola oil; season with salt and pepper, to taste. Add corn to grill; cover and cook, turning occasionally, until husks are slightly charred and corn is tender, about 12-15 minutes.
Peel down husks and spread with butter mixture.
Serve immediately with lime wedges.