Cook the pasta according to package directions, making sure not to overcook it.
While the pasta is cooking, take a cutting board and small sharp knife and cut each olives into quarters. Put the quartered olives either in a medium-sized bowl or use the empty olive can they came in.
Take out the sun dried tomatoes and remove the excess oil by pressing them into paper towels. Using the cutting board and sharp knife, cut them into small pieces. Set aside with the olives.
Wash and dry the scallions, then using the same cutting board and knife, slice the green parts into small circles. Discard the white part and place the green slices in with the tomatoes and olives.
Once the pasta has cooked, put it into a large colander and run cold water over it to stop the cooking process. After it's rinsed and drained, put it into a large mixing bowl and set aside.
Rinse the shrimp off in the colander with cold water, then drain and set them on a large plate lined with paper towels to soak up any excess moisture.
Place the olives, tomatoes, and scallions in with the pasta. Add in the shrimp once it’s drained.
In the same bowl that held the olives, tomatoes, and scallions (or a new bowl if you used the can), measure out the mayonnaise, lemon juice, and kosher salt with measuring spoons and cups, then mix them all together with a small whisk or spoon.
Pour the dressing into the mixing bowl with the pasta and mix everything together with a pair of large tongs. You will need to mix very well to make sure all ingredients are integrated.
Notes
- Can be made the night before and will store for 36 to 48 hours. After that the pasta may start to get mealy.