Prepare the Corn: If using fresh corn, grill or boil it until tender, about 5–7 minutes. Let it cool slightly before cutting the kernels off the cob. If using frozen, cook according to package instructions.

Sauté the Corn: In a large skillet, heat olive oil over medium heat. Add corn kernels, salt, pepper, and chili powder. Sauté for 5–7 minutes until charred. Remove from heat and cool.

Make the Dressing: Whisk together mayonnaise, sour cream, and lime juice in a medium bowl until smooth and creamy.

Combine the Ingredients: In a large mixing bowl, combine cooled corn, cotija cheese, and cilantro. If using, fold in diced avocado.

Dress the Salad: Drizzle the dressing over the corn mixture and toss gently to coat thoroughly.

Serve and Garnish: Transfer to a serving dish, garnish with more cotija cheese and cilantro. Serve immediately or let chill for 30 minutes.