Mexican Chicken Pasta Salad

I just made this salad and really like it, especially the dressing. You can get creative with what you add/omit. I made it without the green pepper, cheese, lettuce and cilantro. I added a can of kidney beans. This recipe is from a favorite online recipe site of mine - here's the link directly to this recipe if you want to see a photo (it's a pretty salad) http://www.recipezaar.com/53495

Ingredients
8 ounces penne pasta (2 cups uncooked)
2 cooked chicken breasts, diced (about 2 cups)
1 (8 3/4 ounce) can whole kernel corn, drained
1 small zucchini, cut in half lengthwise, then sliced
1-2 stalk celery, sliced thin
1 medium sweet red pepper, sliced
1 medium green pepper, sliced (optional)
4 green onions, sliced
1 (4-7 ounce) can green chilies
1/2-1 cup shredded cheddar cheese (optional)
2 cups lettuce, chopped
1/4 cup chopped cilantro

Dressing
3/4 cup mayonnaise
1/4 cup sour cream or yogurt
2 tablespoons ReaLime juice
2 teaspoons sugar
1/2 teaspoon salt
3/4 teaspoon cumin
1/2 teaspoon chili powder

Directions

1. Cook pasta according to package directions, drain, rinse, and set aside.
2. Combine all vegetables in a large bowl.
3. Combine all dressing ingredients; stir thoroughly.
4. Pour dressing over salad; toss to coat.
5. Chill 1 hour, then serve.

Note: Instead of mixing lettuce into salad, you can layer it on top to keep it from wilting.