Place the eggs in a medium saucepan and cover them with water. Bring to a boil over medium-high heat. Once boiling, cover the saucepan, remove it from the heat, and let the eggs sit for about 12-15 minutes.
After the eggs have cooked, drain the hot water and transfer the eggs to an ice bath or run them under cold water until cool. Peel the eggs once they are cool enough to handle.
In a mixing bowl, mash the avocados with a fork until smooth. Stir in the lemon juice, Dijon mustard, garlic powder (if using), and season with salt and pepper to taste.
Chop the cooled, peeled eggs and add them to the avocado mixture. Fold in the chopped red onion and celery gently to combine.
Taste and adjust seasonings as needed. Garnish with fresh herbs if desired.
Serve the avocado egg salad on whole grain bread, crackers, or lettuce wraps.