In a large bowl, whisk the lemon juice, the anchovy paste, if using, and the garlic paste. Whisk in the EVOO until thickened. Add the cooled potatoes, the tomatoes, celery, onion, parsley, caperberries, olives and chile; season with pepper and toss to combine. Add the tuna to the salad and toss gently to flake it. Squeeze the lemon wedges over the salad.