Bring a large pot of salted water to a boil. Meanwhile, heat a large skillet over medium heat and add the scallion greens and sun dried tomatoes and sauté for a minute then add the fresh tomatoes, tuna, vinegar and the red pepper flakes. Sauté around for a couple of minutes and keep warm as you finish the dish.

Cook the pasta till al dente. Remove 1/4 cup (60 ml) of the starchy pasta water and reserve. Do not overcook the pasta as it will be going in the skillet to cook as well.

Drain pasta well, then add the pasta to the skillet, now over low-medium heat, and toss well with the sauce. By eye add about half of the parsley and the Parmesan and keep tossing until cheese is melted - this will happen in less than a minute. Add reserved pasta water if, and only if, the sauce needs some liquid. Some tomatoes will be very juicy and you might not need the water. Taste the sauce and season with salt and pepper as desired. Divide the pasta in warm bowls and garnish with remaining parsley and Parmesan.