Begin by washing and dicing the large tomatoes, ensuring to scoop out the seeds to prevent excess moisture. Thinly slice the small cucumber and chop the red onion. Place all these freshly chopped vegetables along with finely chopped fresh parsley into a large mixing bowl.

Gently open the package of Albacore tuna and drain any excess liquid. Flake the tuna and add it to the bowl with the vegetables. Use a fork to break it into smaller pieces.

In a small bowl, combine two tablespoons of olive oil and one tablespoon of freshly squeezed lemon juice. Whisk them together until well blended.

Sprinkle salt and pepper over the salad to enhance the overall taste. Gently toss the ingredients together until everything is evenly coated with the dressing.

Serve it immediately for a delightful lunch or picnic dish, or cover and refrigerate for about 30 minutes before serving.