Dice the pancetta, onion, carrots and celery. Mince the garlic.
In a large dutch oven or braiser, heat a tbs of olive oil over medium heat and saute the pancetta for ~5 minutes, until crisp. Remove and set aside.
In the same pot / pan, add the onions, carrots and celery, a large pinch of kosher salt and a few grinds of cracked black pepper. Stir and cook for about 7 minutes, until they have softened. Add the tomato paste and chili flakes and mix to combine. Cook for a minute until the tomato paste has caramelized.
Add the beef, a tsp of kosher salt and 1/2 tsp of cracked black pepper. Cook for ~5 minutes, until it's no longer pink.
Add the garlic and fresh thyme leaves. Stir for 30 seconds until the garlic is fragrant. Add the wine. Let it come to a boil, reduce the heat to medium low. Stir to combine. Let the wine reduce until almost all of the liquid has evaporated.
Add the crushed tomatoes, chicken stock, bay leaves, a large pinch of kosher salt and a few grinds of cracked black pepper. Let it come to a boil. Reduce the heat to low and partially cover. Cook for 45 minutes.
Meanwhile bring a large stock pot filled with water to a boil. Once it's boiling, add 1/4 cup of kosher salt. Let it return to a boil. Drop the pasta when the bolognese has ~10 minutes left. Stir and cook until it's al dente (2 minutes under the suggested cooking time).
After 45 minutes, add the heavy cream or milk, nutmeg, and a small handful of basil. Stir and cook for another 15 minutes.
Add the pasta to the bolognese and 1/4 cup of pasta water. Mix to combine for a few minutes.
To serve, add the pasta bowls, shower with freshly grated parm and basil.