In a small bowl, whisk together mayonnaise, olive oil, lemon juice, Dijon mustard, salt, and pepper until well combined and creamy.

Drain and rinse the canned chickpeas under cold running water for about 30 seconds, then pat them dry.

Transfer the rinsed chickpeas to a mixing bowl and mash them lightly with a fork.

Add the flaked tuna, diced celery, chopped red onion, capers or olives, and fresh dill into the bowl.

Pour the prepared dressing over the chickpea mixture and stir gently until well-coated.

You can serve the salad immediately or refrigerate it for at least 30 minutes before serving.