Trim the celery stalks, removing any tough ends and strings. Slice them thinly on a diagonal for visual appeal and maximum crunch.
In a large bowl, whisk together lemon juice, extra-virgin olive oil, salt, and freshly ground black pepper until well emulsified.
Add the sliced celery to the bowl with the dressing and toss to coat evenly. Allow to marinate for 5 minutes to slightly soften and absorb flavors.
If using any optional add-ins like Parmesan, pine nuts, or shallots, gently fold them in now, reserving a small amount for garnish.
Sprinkle chopped fresh parsley over the salad and toss gently to incorporate.
Taste and adjust seasoning as needed, adding more salt, pepper, or lemon juice to balance the flavors.
Serve immediately for maximum crispness, or chill for 15 minutes for a colder texture. Garnish with additional parsley and any reserved add-ins just before serving.
