Prep the corn. If using fresh corn, shuck it and cut the kernels off the cob. For frozen, thaw and pat dry. For canned, drain and pat dry. Removing excess moisture helps you get a better char.

Char the corn. Heat a large skillet or grill pan over medium-high. Add a little oil or butter, then add corn in a single layer. Cook undisturbed for 2–3 minutes to get some color, then stir and cook another 3–5 minutes until you see charred spots. Work in batches if needed so the pan isn’t crowded.

Cool slightly. Transfer the corn to a large bowl and let it cool for 5–10 minutes. Slightly warm corn helps the flavors meld, but you don’t want it piping hot or the dressing will thin out.

Make the dressing. In a small bowl, whisk together mayonnaise, sour cream, lime zest, lime juice, garlic, chili powder, smoked paprika, a pinch of cayenne or a dash of hot sauce, and a good pinch of salt and pepper. Taste and adjust the seasoning.

Combine. Pour the dressing over the warm corn. Add crumbled cotija, chopped cilantro, green onions, and jalapeño if using. Toss gently until everything is coated and evenly distributed.

Finish and serve. Taste again and add more lime, salt, or heat as needed. Sprinkle extra cotija and a pinch of chili powder on top for a pretty finish. Serve slightly warm or at room temperature.