Gather the veal and pork. Very finely chop the pancetta or cut it into quarters and then pulse it in a food processor until ground. Once the vegetables are translucent, add all of the meat and increase the heat to high. Let the meat brown, stirring frequently, for about 15 minutes.
While the meat cooks, gather white wine, milk, tomato paste and thyme. Once the meat has browned nicely, add the tomato paste and stir to combine. Then add the white wine, milk and fresh thyme. Stir again, scraping the bottom if needed. Let everything come just to a boil, then reduce the heat to low and let simmer for 1 to 1 1/2 hours.
As the ragu cooks, remember to stir it occasionally, to prevent it from sticking or scorching.