Step 1: Prepare the Tuna: Thoroughly drain the canned tuna, ensuring excess water is removed. Flake the tuna into a medium-sized mixing bowl using a fork. Be sure to break up any large chunks for a more uniform texture.
Step 2: Combine Wet Ingredients: In a separate small bowl, whisk together the mayonnaise, lemon juice, and Dijon mustard until well combined. This ensures a smooth and creamy base for the tuna salad.
Step 3: Add Vegetables and Herbs: Gently fold the diced red onion, celery, and fresh parsley into the flaked tuna. If desired, include the optional chopped dill pickle or sweet pickle relish for added flavor and texture.
Step 4: Incorporate Dressing: Pour the mayonnaise mixture over the tuna and vegetable mixture. Carefully fold all ingredients together until evenly coated, avoiding overmixing to maintain the tuna's texture.
Step 5: Season and Adjust: Season the tuna salad with salt and freshly ground black pepper to taste. Adjust the lemon juice or mustard to achieve the desired level of tanginess or sharpness.
Step 6: Chill and Serve: Cover the tuna salad and refrigerate for at least 30 minutes to allow the flavors to meld. Serve chilled on bread, crackers, lettuce wraps, or as desired.
Optional: For a spicier kick, add a pinch of red pepper flakes. If you prefer a sweeter tuna salad, use sweet pickle relish instead of dill pickle relish. Avocado can be used as a substitute to mayonnaise.