Best Bolognese sauce out there

From Bon Appetite magazine
It doesn’t take a lot of ingredients (or a lot of money) to make a classic Bolognese recipe. What it does take, though, is patience for the sauce to achieve the ideal authentic texture. You’re going to go low and slow—it’ll take around 3 hours, but most of that cook time is hands-off.

1 medium onion, chopped
1 celery stalk, chopped
1 small carrot, peeled, chopped
3 tbsp extra-virgin olive oil
1 lb ground beef (20% fat), patted dry
Kosher salt
3 oz. thinly sliced pancetta, finely chopped
1 cup dry white wine
⅓ cup tomato paste
1 bay leaf
Pinch of finely grated nutmeg
2 cups (or more)chicken broth
1 cup whole milk
1 lb. fresh tagliatelle, pappardelle, or dry rigatoni
3 oz. finely grated Parmesan (about ½ cup), plus more for serving

Pulse the onion, celery, and carrot in a food processor until very finely chopped. Transfer to a small bowl.

Heat the oil in a large pot over medium.
Break the beef into small clumps (about 1½”) and add to pot; season lightly with salt. Cook, stirring occasionally but not breaking meat apart, until beef is lightly browned but not crisp, 6–8 minutes. It may be gray in spots (that’s okay!) and still a little pink in the center. Using a slotted spoon, transfer beef to a medium bowl.

Wipe out the pot. Cook the pancetta in pot over medium heat, stirring occasionally, until pancetta has released some of its fat and is crisp, 6–8 minutes. Add onion mixture to pot and cook, stirring occasionally, until vegetables are very soft and beginning to stick to surface, 6–8 minutes.

Return the beef to pot and pour in the wine. Reduce the heat to medium-low and cook, smashing down on beef with a wooden spoon, until wine is evaporated, surface of pot is almost dry, and meat is finely ground, 12–15 minutes. (The meat should be reduced to what looks like little bits. It takes a bit of effort, but you can take breaks.) Add the tomato paste, bay leaf, and nutmeg and cook, stirring occasionally, still pressing down on meat, until the tomato paste is slightly darkened, about 5 minutes.

Pour the stock and milk into the pot; add a pinch of salt. Reduce the heat to the lowest setting and cook, uncovered and stirring occasionally, until the meat is very, very tender, 2–2½ hours.
There shouldn’t be any rapid bubbles at this stage. Instead, the sauce should release the occasional small bubble or two. When finished, the sauce should have the texture of and look like a sloppy joe mixture. If the liquid reduces before the meat is completely tender, add an extra ½ cup stock and continue cooking. Discard bay leaf. Taste sauce and adjust seasoning with salt; keep warm.

Cook the pasta in a large pot of boiling salted water. If using fresh pasta, cook about 3 minutes. If using dry, cook until very al dente, about 2 minutes less than package directions.

Using tongs, transfer the pasta to the pot with the sauce. Add 1 cup pasta cooking liquid and ½ cup Parmesan. Increase the heat to medium, bring to a simmer, and cook, tossing constantly, until pasta is al dente and liquid is slightly thickened, about 2 minutes.

Transfer the pasta to a platter and top with more Parmesan.

Do Ahead: The sauce can be made 4 days ahead. Cover and chill.