Prep the chickpeas. Drain and rinse them well. Pat dry with a clean towel so the dressing doesn’t get watery.
Mash to the right texture. Use a fork or potato masher to crush the chickpeas in a bowl. Leave some chunks for bite, but aim for a mostly mashed, spreadable mix.
Add crunch and herbs. Stir in the celery, red onion, pickles or relish, and your chopped dill or parsley.
Make the dressing. In a small bowl, whisk the mayo, yogurt (if using), Dijon, and lemon juice.
Add garlic powder, smoked paprika, black pepper, and a pinch of salt.
Combine and adjust. Fold the dressing into the chickpea mix. Taste and adjust salt, lemon, or mustard until it pops with flavor.
Toast the bread (optional but great). A light toast adds crunch and helps the bread hold up.
Assemble the sandwiches. Layer greens on the bread, then pile on a generous scoop of chickpea salad. Add tomato, cucumber, or avocado if you like.
Top with the second slice.
Serve or chill. Eat right away, or chill the salad for 30 minutes to let the flavors meld.