Cook the pasta in salted water until al dente. Drain and rinse under cold water. Toss with olive oil to prevent sticking.
Grill or roast the corn until lightly charred. Let cool and cut kernels off the cob.
In a bowl, whisk together mayo, sour cream, lime juice, chili powder, garlic powder, salt, and pepper.
In a large mixing bowl, combine pasta, corn, and dressing. Add cheese, cilantro, and jalapeño. Mix well.
Chill for 15-30 minutes before serving. Garnish with extra cheese, lime juice, or hot sauce if desired.
Notes
To adjust spice level, tweak the amount of jalapeño or chili powder. For a protein boost, add grilled chicken or shrimp. Vegan versions can use dairy-free mayo and cheese.