Prepare the Tuna: Drain the canned tuna and transfer it to a mixing bowl. Use a fork to break up any large chunks.
Add Ingredients: Add chopped celery, red onion, and any optional add-ins to the bowl with the tuna.
Mix Dressing: In a separate small bowl, mix together mayonnaise, Greek yogurt (if using), lemon juice, salt, and pepper. Adjust the amount of mayo and lemon juice to your taste preferences.
Combine: Pour the dressing over the tuna mixture in the bowl.
Mix Thoroughly: Gently fold the ingredients together until the tuna and veggies are evenly coated with the dressing.
Chill (Optional): You can chill the tuna salad in the refrigerator for about 30 minutes before serving to let the flavors meld.
Serve: Enjoy the tuna salad on its own, as a sandwich filling, on crackers, or with salad greens.