Preheat oven to 325° F. Liberally salt and pepper the pork roast. Add olive oil and butter to large Dutch oven and heat over medium-high until butter melts, but does not burn. Add pork roast to pan and brown on all sides, about 8 to 10 minutes in all.
Add the onion and garlic and saute for 1 minute. Add tomatoes, wine, thyme, oregano, fennel, and hot sauce and bring to a boil. Cover, and put in oven.
Braise for 3 to 4 hours, turning every hour or so. Add more liquid (water, wine, or tomato sauce) if needed. (The liquid should come to about 1/3 of the way up the pork.) Meat is done when it’s practically falling apart. Put on a cutting board (remove the sprigs of herbs at the same time) and pull it apart with two forks, then add back to pot and stir.
Cook 1 to 2 pounds pasta according to package directions. When it’s is ready, put into individual bowls and top with ragu and lots of Parm. Alternately, toss the pasta with the ragu and a bit of pasta cooking water, as needed, and top with Parm.