Sauté sausage crumbles in a large pan or dutch oven over medium-low heat.
Add minced onion, carrot, and celery, and parsley to the pan.
Add canned tomatoes and their juice.
Bring to a simmer then add thyme and rosemary
Continue simmer uncovered for 20 minutes, until thickened.
Mix tomato paste with 1 cup of hot water.
Cook about 10 minutes until the sauce is dark red and glistens with oil.
Remove herb sprigs and add pepper to taste.
Meanwhile, boil large pot of salted water then cook and drain the pasta.
Serve ragù over plate of pasta and top with grated parmesan cheese;