Cut the corn off the cob (see video for how I do this without getting corn everywhere!) If using frozen, do not thaw. Heat 1 tbsp oil in a skillet over high heat. Add half the corn and shake to spread it out. Cook, stirring / tossing occasionally, for 3 minutes (4 minutes for frozen corn) or until you get nice charred bits on both sides and the corn is just cooked (it cooks more with residual heat). Avoid stirring too often so you get nice brown bits. Transfer into a bowl. Add remaining oil in the fry pan and cook the remaining corn, then add it into the bowl. Add mayonnaise, sour cream and parmesan. Stir to combine. Add remaining ingredients. Adjust lime juice and salt to taste. Serve warm or at room temperature.