Heat a large dry skillet over medium-high heat and cook corn for 5 to 7 minutes, stirring occasionally, until some kernels develop browned spots. Transfer to a plate to cool.
Boil rotini in water with the tablespoon salt until fully tender. Drain, rinse briefly under cool water and drain thoroughly.
Whisk oil, lime juice, cumin, dressing salt and pepper in a large bowl. Add pasta, cooled corn, beans, bell pepper, jalapeño and red onion.
Toss thoroughly, then fold in cilantro. Serve cool or cover and refrigerate promptly for at least 30 minutes.
Stir before serving and refrigerate leftovers within 2 hours.