Heat the oil in a large cast-iron skillet over medium high heat until it starts to shimmer, then add the corn. Flip with tongs until just beginning to char on all sides, about 10 minutes. Remove from the pan and allow to cool until manageable to touch. Cut the kernels off the cob and add to a medium bowl.
Add the tomatoes, lime juice, cilantro and jalapeños and fold gently to combine. Season with salt and pepper.