Sour cream and mayonnaise are overused in my opinion.  I can substitute plain greek yogurt and my family doesn't notice unless they catch me in the act. :)  Try it at your house and see. It's an easy way to keep the dish "clean" and cut the calories.  Who wants all those chemicals in their body anyways and makes it pointless to have a "healthy salad" all ladened with processed stuff, right?  Humor me and try this...

Ingredients:
2 cups cooked chicken, shredded into large pieces
2 medium avocados, diced
2 TBSP fresh squeezed lime juice (you'll divide this later)
salt, to taste
1/4 cup thinly sliced green onion
1/2 cup finely chopped fresh cilantro (or chop it more coarsely if you prefer)
2 TBSP plain greek yogurt *this keeps it 21-Day Fix, 80 Day Obsession & Shift Shop compliant

Instructions can be found HERE.