01 - Cook the pasta in a large pot of salted boiling water according to package instructions until al dente. Drain, rinse with cold water, and set aside to cool.
02 - Preheat grill or large skillet over medium-high heat. Lightly oil corn and cook, turning occasionally, until charred and tender (8-10 minutes). Let cool, then cut kernels from cobs. If using 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.
04 - Add cooled pasta, corn kernels, bell pepper, red onion, jalapeño, and cilantro to bowl. Toss well to coat everything evenly in dressing.
05 - Gently fold in crumbled cotija cheese. Taste and adjust seasoning as needed.
06 - Chill salad for at least 15 minutes before serving. Garnish with extra cilantro, lime wedges, and sprinkle of chili powder if desired.