Cook pasta according to package directions until al dente. Drain and then rinse under cold water.
While pasta is cooking, prepare the dressing. In a large bowl, combine mayonnaise, sour cream, taco seasoning, garlic powder, salt, and pepper. Mix well.
Add drained pasta, tomatoes, corn, black beans, cheese, and cilantro. Stir well to combine. Add more salt, pepper, and/or cilantro if needed.
Refrigerate for at least 2 hours before serving so that flavors can deepen and pasta chills.
Notes
Taco pasta salad will last in the refrigerator for up to five days.
See my tips and tricks for making this pasta salad above the recipe box.