In a large pot bring water to a boil. Place the tomatoes that have been scored with a knife on the bottom and around them. Boil for 5 minutes or until the skin is peeling off the tomatoes. Remove from heat, peel and dice.
In a large pot over medium heat, add the oil, the onion and the parsley and cook until the onion is translucent.
Add the tomatoes to the onion mixture and cook for 15to 20 minutes. Salt and pepper.
Add the whole cherry tomatoes and cook for another 3 minutes or until the cherry tomatoes are tender.
Bring a large pot of salted water to a boil. Add the linguine and cook until al dente. Drain and place the cooked linguini back in the pot, and add 2 table spoons of butter and mix well.
Place the pasta in a large bowl, add the tomatoes sauce and cover with Pecorino cheese.