Preheat your oven to 300F.
Add the canned tomatoes (with juices) to a large bowl and use your hands to break the whole tomatoes up.
Season the short ribs with salt & pepper (use half the salt and save the rest for the sauce).
Add the olive oil to a Dutch oven over medium heat, and once the pot is hot, sear half the short ribs for about 3-4 minutes/side or until browned. Transfer to a plate and then repeat for the second batch. The ribs may release a fair bit of fat, and if they do, spoon some of the excess fat out, leaving about 1-2 tablespoons in the pot.
Add the carrots and onions to the pot and sauté for 6-8 minutes or until they start to lightly brown.
Stir in the garlic and tomato paste and cook for 1-2 minutes, stirring often.
Stir in the red wine and scrape up any browned bits from the bottom of the pot. Bring it to a simmer.
Add the beef broth, tomatoes, rosemary, remaining salt, and oregano to the pot and give it a good stir. Add the short ribs in as even of a layer as possible (some will likely stick out and that's fine), and top with the thyme sprigs. Cover and transfer to your oven and cook for 3-3.5 hours (the meat should fall off the bone).
Once the ribs are done, skim the fat off the surface (I use a spoon to do this... don't worry about getting it all). Discard the thyme sprigs. Transfer the short ribs to a large bowl and remove any bones or large fat/gristly pieces, and then shred the meat with two forks. Add the shredded meat back to the pot.
Stir in the cream if using, and let it warm through. Give it a taste and season with extra salt & pepper as needed.
I like to slightly undercook the pasta and then stir it right into the ragu and let it cook for a few minutes to help infuse more flavor into the noodles. If you want to have 6 servings at once, cook 1 lb. of pasta (I recommend pappardelle). If you don't want to do it all at once, take some of the sauce out (to freeze etc.) and serve with your desired amount of pasta.