Prepare the corn according to the package directions and let cool slightly.
In a small mixing bowl, stir together ⅓ cup mayonnaise, ⅓ cup sour cream, 2 tablespoons lime juice, 1 teaspoon chili powder, ½ teaspoon smoked paprika, 1 clove minced garlic, and salt and pepper to taste.
Add in the 4 cups of cooked corn kernels, ¼ cup chopped fresh cilantro, 3 green onions, and most of the ½ cup cotija cheese, if using, and stir to combine.
Taste and adjust: Add more lime, chili powder, or salt as needed and top with extra cotija and cilantro. Serve warm, at room temperature, or chilled.