Finely mince your onion, carrots, celery; you want about 1 cup of each. Mince the garlic. If you have a food processor, use it: the mince should be very small.
Add the olive oil to a very large heavy bottomed pot or dutch oven and heat over medium. Add the onions, carrot, celery, and garlic and cook, stirring, until very soft, but not brown.
Stir in the anchovies, breaking them up. Add the wine, stir to deglaze and cook over high heat until the wine is mostly evaporated.
Stir in the chicken stock, milk, and tomato paste. Add the meats, making sure they’re broken up in the liquid. We’re not browning the meats, instead opting for a very tender, slow braise. Add the bay leaf and bring to hard simmer, the reduce the heat to a bare simmer. Simmer for 6 hours, partially covered, checking on it every hour or so to make sure it hasn’t gone dry. Add stock as necessary.
After simmering, the liquid should be almost completely reduced and the sauce should be thick and luscious. Stir in the cheese and season with salt to taste.
To sauce: Cook your pasta 1-2 minutes before the time indicated on the package. Transfer 1/2 cup sauce per portion to a nonstick skillet and toss your pasta in the skillet for 1-2 minutes over medium heat.
Serve with extra cheese and chili flakes.