Place a large, heavy bottomed pan over medium heat. Add the olive oil, and add the duck, pork and pancetta. Season with salt and black pepper. Cook over medium-high heat until the meat begins to brown, about 5-7 minutes. Add the onion, celery and carrots, cooking for 5 minutes more until vegetables start to soften. Add the ancho chile, garlic and cook 1 minute more. Add the wine, bay leaves and thyme. Cook until wine evaporates and the mixture begins to brown. Be sure to scrape the brown glaze off the bottom of the pan. Add 1 cup of the chicken stock, half of the veal stock and all the tomato paste. Cook at a slow simmer, partially covered until liquid begins to thicken. The next few steps take 30-40 minutes and are what gives the sauce a rich texture and depth of flavor. Add milk 2 tablespoons at a time, stirring the sauce well to incorporate.
Continue to cook the sauce gently, adding a few tablespoons of milk when needed. Reduce until the sauce begins to brown again. Add the remaining veal stock, stirring and scraping well. The sauce is done when its texture is velvety and the meat is completely tender, about 1 ½ hours.
Enjoy with a glass of Cakebread Cellars Syrah.