Begin by bringing a large pot of salted water to a rolling boil. Add the capellini pasta and cook for about 5 minutes until al dente. Drain and rinse under cold water.

In a mixing bowl, combine lemon juice, olive oil, garlic salt, and black pepper. Whisk until well emulsified.

Add the cooled pasta to the dressing and ensure it is well-coated. Fold in the diced tomatoes and capers.

Sprinkle in parsley and add lemon zest; toss again to combine.

Allow the salad to chill for about 30 minutes before serving.