Boil the pasta according to the package instructions. Once cooked, drain and let it cool to room temperature.
In a mixing bowl, stir together all the ingredients for the dressing: mayonnaise, yogurt, mustard, and spices until well combined.
Finely chop the celery and red onion, and mince the parsley. Add them to the bowl.
Add the drained tuna on top, and gently mix. Use a fork to mix everything together, while breaking up any large pieces of tuna. You can serve it immediately or let it cool in the fridge for at least an hour for all the flavors to meld and combine. Enjoy!
Storage instructions
In the fridge: Once assembled, store the salad in an airtight container in the fridge for 3-4 days, stirring it well between each time you serve.
Notes
Leave it to rest: I recommend letting the salad sit in the refrigerator for at least 30 minutes after assembling it to allow the flavors to meld. This produces a better, more well-rounded flavor.
Experiment with veggies: You can choose from plenty to add flavor, color, and texture to the salad. I love using it as an excuse to clear out my fridge. You can use pickles, cucumber, bell pepper, cherry tomatoes, carrots, avocado, capers, olives, etc.
Tweak it to your liking: You can easily adjust any of the flavors in the dressing, the size of the chopped veggies, the type of pasta, etc., to suit your dietary and flavor preferences.