Rinse and drain the chickpeas. Add to a mixing bowl and lightly mash with a fork for texture.
Chop the onion, celery and pickles finely. Mince the garlic.
Add the remaining ingredients into the bowl, and mix well with a spoon. Taste and adjust seasonings if needed.
To assemble the sandwich, toast 2 slices of bread and and prepare any other sandwich toppings you desire (tomato, lettuce, cucumber).
Scoop a good amount of filling onto both slices of bread, add desired toppings on one slice and top with other.
You can store the chickpea mixture in a air-tight container in a fridge for at least 3-5 days and make easy, quick sandwiches when in a hurry.