For the pork ragu

1. Prep pork. Trim and discard any large sections of fat from the pork shoulder, then cut the pork shoulder into 1 1/2 inch pieces. Season pork with salt and pepper.
2. Sear pork. Heat oil in a large heavy pot over medium heat. When oil is shimmering, add pork and brown the pieces on all sides, 10–12 minutes total. Transfer to a plate. Set aside.
3. Cook aromatics. If there is a lot of fat in the pan, drain all but 2 tablespoons of fat from the pan. Add onions and garlic and cook, stirring occasionally, until golden brown, 8–10 minutes. If pan is dry, add a splash of wine to help deglaze the pan. Add tomato paste and cook, stirring occasionally, until slightly darkened in color, about 2 minutes. Add wine and simmer for 2 minutes, scraping up any browned bits.
4. Add ragu ingredients. Add tomatoes, rosemary, thyme and bay leaf; stir in water or broth. Add pork along with any juices accumulated on the plate.
5. Simmer. Bring mixture to a boil. Then cover, reduce heat, and simmer, adding more water or broth as needed, until meat is very tender, 1 1/2 to 2 hours.
6. Shred meat. Discard bay leaf and thyme sprig. Using 2 forks, shred meat in pot; taste and season with salt and pepper.

For the polenta

1. Whisk. Whisk together broth and polenta in a large, microwave-safe bowl.
2. Microwave. Cover bowl with wax paper and cook in microwave on High until thickened, about 15 minutes, whisking every 5 minutes to combine.
3. Finish. Stir in butter, pepper, and crème fraîche (if using). Taste and adjust for salt and pepper.

For serving

1. Serve. Divide polenta among 4 plates. Top with pork ragu, chopped parsley and grated Parmesan. Serve immediately while the polenta is still soft.