Heat oil over medium heat. Add frozen corn and let cook until corn starts to char, stirring occasionally (it took about 7-8 minutes before my corn was lightly charred).
While the corn is cooking, mix together mayonnaise, cheese, lime juice, cilantro, red onion, garlic, chili powder, and salt and pepper in a large bowl.
When corn is done, gently fold it in with other ingredients.
Serve immediately and store any leftovers in the refrigerator.