Note: This sauce can be made with either beef or pork. Pork butt roast is often labeled Boston butt in the supermarket. To prevent the sauce from becoming greasy, trim the meat well and drain off most of the fat from the skillet after browning. This thick, rich, robust sauce is best with tubular pasta, such as ziti, rigatoni, penne, or garganelli. (For fresh garganelli, we recommend using our Fresh Pasta Without a Machine recipe.) Pass grated Pecorino Romano (especially nice with pork) or Parmesan cheese at the table.

Heat oil in 12-inch skillet over medium-high heat until shimmering. Sprinkle meat with ½ teaspoon salt and pepper and brown on all sides, turning occasionally with tongs, 5 to 7 minutes. Transfer meat to large plate; pour off all but 1 teaspoon fat from skillet. Add onion and remaining ¼ teaspoon salt and cook until softened, 2 to 3 minutes. Add wine and simmer briskly, scraping up any browned bits, until wine reduces by half, about 2 minutes.

Return meat and any accumulated juices to skillet; add tomatoes and reserved juice. Bring to boil, then reduce heat to low; cover; and simmer gently, turning meat several times, until meat is very tender, 1½ to 2 hours for pork and 2 to 2½ hours for beef. (If beef isn’t tender after 2 hours, add ¼ cup water and continue to cook until tender.)

Transfer meat to clean plate. Using 2 forks, shred meat into bite-size pieces, discarding any large pieces of fat or connective tissue. Return meat to skillet. Return sauce to simmer over medium heat and cook, uncovered, until slightly thickened, about 5 minutes. Season with salt and pepper to taste.

Bring 4 quarts water to boil in large pot. Add pasta and 1 tablespoon salt and cook, stirring often, until al dente. Reserve ½ cup cooking water, then drain pasta and return to pot. Add sauce to pasta and toss to combine, adjusting consistency with reserved cooking water as needed. Serve. (Sauce can be refrigerated for up to 4 days or frozen for up to 2 months.)