Season the meat with salt and pepper. Heat the oil in a large Dutch oven over high heat. Sear the meat all over, about 2 minutes per each side.
Move the meat to the side (or remove it from the pot altogether if necessary), add the celery, carrot and onion and brown the vegetables, stirring occasionally, about 3 minutes.
Add the garlic and cook for a minute or 2 longer. Add the wine to deglaze the pot, scraping up the browned bits on the bottom. Add the tomatoes, water and bay leaves (and the meat if you removed it). Bring the liquid to a simmer and taste for seasoning. Add more salt if necessary. Cover the pot and bake, basting the meat occasionally, until tender, about 3 hours.
About 20 minutes before the meat is tender, bring a pot of water to a boil and salt liberally. Add the shells, give it a stir and cook until al dente according to the package instructions. Drain the pasta.
To serve, you can pull the meat apart with a couple of forks right in the pot at the table. Serve with the pasta, plenty of sauce and vegetables, tossing them all together.
For more ingredient substitution ideas, see the article below.