01 - Bring a large pot of salted water to a boil. Add pasta and cook according to package directions until al dente. Drain well, rinse with cold water to stop cooking, and set aside to cool completely.
02 - Preheat grill or large skillet over medium-high heat. Lightly oil corn ears and cook, turning occasionally, until charred in spots and tender, about 8–10 minutes. Let cool, then cut kernels from cobs. For frozen corn, sauté in dry skillet until lightly golden.
03 - In a large mixing bowl, whisk together mayonnaise, sour cream, lime juice, chili powder, smoked paprika, cumin, salt, and black pepper until smooth and well combined.
04 - Add cooled pasta, corn kernels, bell pepper, red onion, jalapeño, and cilantro to the bowl with dressing. Toss thoroughly until all ingredients are evenly coated.
05 - Gently fold in crumbled cotija cheese. Taste and adjust seasoning with additional salt or chili powder if needed.
06 - Refrigerate salad for at least 15 minutes to allow flavors to meld. Serve chilled, garnished with additional cilantro, lime wedges, and extra chili powder if desired.