Cook the rotini pasta in a large pot according to package directions until al dente. Drain and rinse under cold water to cool.
If using fresh corn, grill the corn until charred and tender. If using frozen or canned corn, you can skip this step and use it as is.
In a large mixing bowl, combine the cooked pasta, corn, cherry tomatoes, red onion, cilantro, and avocado.
In a separate small bowl, whisk together the lime juice, mayonnaise, sour cream, chili powder, smoked paprika, salt, and pepper until smooth.
Pour the dressing over the pasta mixture and toss to combine until everything is well coated.
Taste and adjust seasoning if needed. For an extra kick, you can add more chili powder or lime juice.
Let the salad chill in the refrigerator for about 15 minutes before serving.
Serve topped with crumbled cotija cheese, if desired.