Bring a large pot of water to boil. Add the asparagus and pasta to the water at the same time, with a generous pinch of salt. Continue to cook until the pasta is cooked through, and then drain and cover the pasta and asparagus with a lid until ready to use.
To a food processor, add the parsley, basil, cilantro, juice from half a lemon, mustard, garlic, Greek yogurt, avocado, water, salt and pepper. Process until smooth, scraping down the sides as needed, for about 5 minutes until smooth.
To a large bowl, add the cooked pasta, asparagus, tuna, sun dried tomatoes, red onion and blended sauce. Toss well to mix everything together.
Divide the pasta salad between three meal prep containers.
Storage, reheating and serving notes: This pasta salad lasts for up to four days in the fridge. It’s best to eat cold or at room temperature, but you can reheat it in the microwave if you want. This meal is not freezer friendly.