Preheat a grill to medium-high heat.

Peel back the husks of the corn, but leave them attached at the bottom. Remove the silk from the corn.

In a small bowl, combine the mayonnaise, sour cream, cotija cheese, cilantro, lime juice, chili powder, salt, and pepper. Mix well.

Brush the corn with the mayonnaise mixture, making sure to cover it evenly.

Place the corn on the grill and cook for about 10-15 minutes, turning occasionally, until the corn is charred in spots and cooked through.

Remove the corn from the grill and let it cool slightly.

While the corn is cooling, soak the wooden skewers in water for at least 10 minutes to prevent them from burning on the grill.

When the corn is cool enough to handle, insert a skewer into the end of each ear of corn.

Serve the corn hot with additional cotija cheese and cilantro on top, if desired.