Start by gathering all your ingredients. Drain the tuna well and place it in your mixing bowl. Chop the red onion, celery, pecans, and parsley, and set them aside.
Using a fork, flake the tuna gently in the bowl. Add in the chopped red onion, celery, and pecans.
Sprinkle in the dill, raisins, and parsley.
Pour in the mayonnaise, and stir everything together until well combined.
Add salt and pepper according to your taste.
Transfer the tuna salad onto a serving platter and garnish with sliced tomatoes.
Your delicious tuna salad is now ready to be served! Enjoy it on its own, in a sandwich, or on a bed of greens.
