Shuck corn and wrap in a single layer of Reynolds Wrap® Heavy Duty Foil to fully enclose the corn then grill corn in foil.
In a small bowl, combine sour cream, mayo, cilantro, minced garlic, garlic powder, cayenne pepper, cumin, and 2 tablespoons fresh lime juice. Stir to blend and set aside.
Partially unwrap corn to cool for a few minutes before applying sauce. Keep the foil under the corn to be used for serving the corn.
Using a basting brush, generously brush on the sauce and sprinkle generously with cotija cheese. Garnish with chili powder and cilantro. Serve with lime wedges.