In a medium bowl, combine the hard boiled eggs and egg whites, avocado, Greek yogurt, lemon juice, green onion, and mustard.
Mash with a fork until desired consistency is reached. Season with salt and pepper, to taste.
Serving suggestions: Spread between two slices of bread for an Avocado Egg Salad Sandwich. Eat with crackers, cut up veggies, on toast, or in a wrap. This salad is best eaten the day it's made.