In a medium mixing bowl, whisk together the mayo, Greek yogurt, lemon juice, mustard, garlic, salt, and pepper until well combined.
Stir in the shredded chicken, craisins, walnuts, celery, and green onions. Check the seasoning and add salt and pepper to taste.
Portion the chicken salad onto lettuce leaves or onto burger buns with some lettuce and serve.
Notes
Nutritional information is for the chicken salad only.
You can use 2-3 cooked chicken breasts instead of a rotisserie chicken. You'll want about 3 cups of shredded chicken in total.
For a less mayo-y flavor, you could use ½ cup mayo and ½ cup yogurt or sour cream.
To toast walnuts: Place the nuts onto a cookie sheet and spread them into a single layer. Bake at 350 degrees F for 8-10 minutes. Remove the nuts from the oven and cool them to room temp.
You don't have to toast the walnuts, but it adds a nice flavor. This can be done ahead of time so they're ready when you are to make the chicken salad.