Heat a gas or charcoal grill to 400F. Clean the grates once it has heated.
In a bowl, whisk together the crema, mayonnaise, cilantro, garlic, chipotle pepper, lime zest and lime juice. Taste and season the mixture with salt if needed. Set aside.
Place the husked corn directly onto grill grates. Grill the corn for about 3 minutes until kernels begin to turn golden brown and look charred. Turn over and repeat. When all sides are browned, remove from the grill onto a plate.
Using a brush or a spoon, coat each ear of corn with the crema mixture. Sprinkle with crumbled cojita cheese. Sprinkle with additional chipotle pepper, if desired. Serve immediately with extra lime wedges.