Cook the pasta according to package instructions until al dente and drain.

In a large bowl, combine the mayonnaise, sour cream, lime juice, and chili powder.

Add the cooled pasta and corn kernels to the bowl, and stir until combined.

Stir in the cotija cheese, cilantro, red onion, and jalapeño (if using), and season with salt and pepper to taste.

Cover and refrigerate for at least 30 minutes to allow flavors to meld.

Before serving, give the salad a quick stir and check for seasoning.