To start, preheat your oven to 425°F (220°C).
Take a medium-sized cast iron skillet and place the corn inside. Drizzle the corn with a generous amount of olive oil and season it with a sprinkle of salt.
Let the corn roast in the oven for approximately 15–20 minutes. Check on it periodically to ensure it becomes charred and tender to your liking.
Whisk together sour cream, mayonnaise, lime juice, chili powder, and salt in a small bowl until the mixture is well blended and the flavors are fully combined.
Once the corn is done roasting, remove it from the oven and let it cool down slightly.
Using a pastry brush, generously coat the roasted corn with the mayonnaise mixture.
Next, sprinkle it with chopped cilantro, cotija cheese, and a dusting of chili powder.
Enjoy every bite of this delightful dish!