If using fresh corn:

1. Heat a large cast-iron skillet over medium-high heat. Add 1 tablespoon of vegetable oil.
2. Working in batches, add corn kernels to the hot skillet in a single layer (avoid overcrowding). Allow corn to char without stirring for 1-2 minutes until golden brown spots appear.
3. Stir the corn and continue cooking for another 2-3 minutes until kernels are tender-crisp with charred spots throughout. Transfer to a large bowl.
4. Repeat with remaining corn kernels and oil.

If using frozen corn:

1. Heat 2 tablespoons of vegetable oil in a large skillet over medium-high heat.
2. Add thawed corn kernels and cook without stirring for 3-4 minutes until they begin to char.
3. Stir and continue cooking for another 2-3 minutes until corn is lightly charred. Transfer to a large bowl.

Assemble the salad:

1. Allow charred corn to cool for about 10 minutes.
2. Add diced red onion, jalapeño, cilantro, and minced garlic to the bowl with corn.
3. In a separate small bowl, whisk together mayonnaise, crema or sour cream, lime juice, lime zest, cumin, chili powder, smoked paprika, salt, and pepper until smooth.
4. Pour the dressing over the corn mixture and toss gently to combine.
5. Fold in half of the cotija cheese, reserving the remainder for topping.
6. Taste and adjust seasoning as needed with additional salt, pepper, or lime juice.