½ cup finely grated Parmesan cheese, plus more for serving
Instructions
In a food processor, pulse the onion, carrot and celery until finely chopped. Transfer to a medium bowl and set aside.
In a large pot, heat olive oil over medium heat. Squeeze off chunks of ground beef, about the size of a golf ball, and add to pot. Season with salt to taste. Cook, stirring occasionally (but not breaking apart the meat), until browned, 6-8 minutes. Using a slotted spoon, transfer beef to a medium bowl and discard grease.
In the same pot, cook pancetta over medium heat, stirring occasionally, until fat renders and pancetta crisps, 6-8 minutes.
Add prepared vegetable mixture and cook, stirring occasionally, until very tender, 6-8 minutes.
Return beef to pot. Add wine and reduce heat to medium-low. Cook, crushing beef with a wooden spoon until finely ground, for 12 minutes.
Add tomato paste, bay leaf and nutmeg and cook, stirring occasionally, until tomato paste begins to darken, about 5 minutes.
Add chicken broth and milk and season with salt. Reduce heat to low until just barely simmering and cook until the liquid reduces and the meat is very tender, about 2 hours. Discard bay leaf and season with additional salt to taste.
Bring a large pot of salted water to a boil. Cook pasta 2 minutes less than al dente according to package directions. Using a slotted spoon, transfer cooked pasta to pot with sauce.
Add Parmesan cheese and 1 cup reserved cooking liquid to pot and stir to combine. Bring to a simmer and cook over medium heat, stirring occasionally, until the liquid has thickened, about 2 minutes. Garnish with additional Parmesan cheese and serve immediately.
Recipe by Two of a Kind at http://www.twoofakindcooks.com/rigatoni-with-beef-bolognese/