Preheat oven to 350 degrees. Place Texas pecan halves on a cookie sheet. Bake 5-8 minutes. Watch carefully they don't burn. Set aside to cool. Combine the 2 cups cooked, chopped chicken, 1/2 cup chopped celery, 1/2 cup chopped red onion, 3/4 cup cubed mango, and 3/4 cup cooled, toasted Texas pecan halves. Cover and refrigerate while making the dressing.
In a small microwave-safe bowl, microwave 2 tablespoons of red pepper jelly on 50% power for 30 seconds until melted. Set aside to cool.
In a small mixing bowl, combine 1/4 cup sour cream, 1/2 cup mayonnaise, 2 tablespoons fresh lime juice,1 tablespoon fresh chopped cilantro, 1 teaspoon cumin, 1/2 teaspoon salt and 1/4 teaspoon black ground pepper. Mix well. Add the 2 tablespoons of cooled, melted red pepper jelly, stirring until completely blended.
Stir the dressing into chicken mixture. Refrigerate at least two or three hours to blend flavors. I like to serve on a bed of lettuce leaves with specialty rolls or crackers.