Heat the oil in a large skillet over medium heat. Add the corn to the skillet and cook for 4-5 minutes or until slightly charred, stirring occasionally. Remove from the heat and cool to room temperature.
Transfer the corn to a mixing bowl. Add the onion, jalapeño, green onion, cilantro and cheese. Set aside.
In a small bowl, whisk together the sour cream, mayonnaise, lime zest, lime juice, cayenne pepper and chili powder. Season with salt and pepper to taste.
Pour the dressing over the corn mixture and toss to coat. Sprinkle with additional cilantro and Cojita cheese, if desired. Serve immediately
Notes
Salad can be made up to 8 hours in advance and refrigerated in an airtight container.