01 - Bring a large pot of salted water to a boil, cook pasta until al dente according to package directions. Drain thoroughly and rinse with cold water. Set aside.
02 - Grill the corn on a preheated grill or grill pan over medium-high heat, rotating until lightly charred and tender, about 8 to 10 minutes. Let cool, then cut kernels from cobs. If using thawed frozen corn, sauté in a dry skillet over high heat until slightly blackened.
03 - In a large mixing bowl, whisk together mayonnaise, sour cream, lime juice, chili powder, smoked paprika, cumin, salt, and black pepper until fully blended and smooth.
04 - Add cooked pasta, charred corn, diced red bell pepper, sliced green onions, chopped cilantro, crumbled Cotija cheese, and jalapeño if desired to the bowl with dressing. Toss gently until all components are evenly coated.
05 - Taste and adjust seasoning with additional salt, pepper, or lime juice as needed. Cover and refrigerate for at least 30 minutes to allow flavors to meld before serving.