Fill a large pot with lightly salted water and bring to a rolling boil. Add ziti and return to a boil. Cook, stirring occasionally, until tender yet firm to the bite, about 10 minutes. Drain.

Meanwhile, heat oil in a skillet over medium heat. Add onion and green pepper; cook and stir until soft, 5 to 7 minutes. Transfer to a bowl.

Cook chicken in the same skillet until no longer pink in the center, 7 to 10 minutes.

Combine salsa, cream cheese, and taco seasoning in a saucepan over low heat; cook and stir until cream cheese is melted, about 5 minutes.

Preheat the oven to 350 degrees F (175 degrees C).

Combine ziti, chicken, salsa mixture, onion mixture, black beans, and corn in a large bowl. Add 1/2 of the Cheddar cheese and mix until combined. Pour into a baking pan.