Bring a large pot of salted water to a boil.
Add the pasta to the boiling water and cook for 2 minutes less than the box instructions. It should be just al dente. Save 1 cup of pasta water before draining.
Chop the sun-dried tomatoes, capers, garlic, and anchovies. Run your knife over the smaller pieces until you get them as fine as possible. Toss the ingredients together in a medium bowl and stir in the oil until a paste forms.
You can use a food processor to save yourself some work.
In a large skillet over medium heat, add sun-dried tomato paste and cook, stirring constantly, until slightly darkened in color, 3 to 4 minutes.
Reduce the heat to medium-low, then slowly whisk in reserved pasta water until a sauce forms. Flake the tuna into large chunks, then add to the sauce along with the oil from the can and the olives. Stir to combine.
Add the pasta and cook for an additional 1 to 2 minutes. Top with the parsley and serve.