Combine chickpeas, cucumber, tomatoes, and red onion in a large mixing bowl.
Whisk lemon juice, olive oil, salt, and pepper in a small jar to create the dressing.
Pour the dressing over the salad and toss thoroughly to coat the vegetables.
Fold in the crumbled feta cheese gently so it retains its texture.
Let the salad sit for 10 minutes before serving to allow flavors to meld.⏱ 10 min
In a medium bowl, combine the drained tuna and mashed avocado, stirring until the mixture is creamy.
Fold in the Dijon mustard, diced celery, and chopped dill until evenly distributed.
Lay the butter lettuce leaves flat on a clean surface or plate.
Scoop the tuna mixture equally into the center of each lettuce leaf.
Roll or fold the leaves like a taco and serve immediately while the lettuce is fresh.