Cook your pasta until al-dente. Do remember to reserve 1/2 cup of the cooking water later on.
While the pasta is cooking, in another pan heat the EVOO.
Brown the onion.
Add in the garlic and sun-dried tomatoes.
Add the tomato sauce and cook for 5 minutes.
Add in your tuna and whipping cream.
Season with salt and pepper and add some of the reserved pasta water.
At this point, you can choose the toss the pasta in the sauce or top the sauce over the pasta.
Sprinkle with grated parmesan cheese before serving.