In a medium bowl, mash the chickpeas with a fork until they are slightly mashed but still chunky.
Add the vegan mayonnaise, celery, red onion, parsley, and lemon juice to the bowl and mix well.
Season with salt and pepper to taste.
Toast your bread or buns if desired.
Serve the chickpea salad on your bread or buns, topped with lettuce, tomato, and avocado if desired. Enjoy your delicious vegan chickpea salad sandwich!