Warm olive oil in a large, heavy-bottomed pot over medium heat. Add onion, celery, carrots and garlic, stirring to coat in the oil. Cook until soft (but not browned), stirring occasionally (8 to 10 minutes).

Increase heat to medium-high, then add bacon, beef and pork, stirring to break up clumps. Cook until all meat is browned (15 - 20 minutes). Add tomato paste, stir to combine and cook for 30 minutes. Be sure you stir occasionally to keep the bottom from burning.

Add milk and cook for 30 minutes, stirring occasionally. Increase heat to high, add wine, bring mixture to a boil and cook until the liquid has evaporated (about 5 minutes). Scrape up any bits that may be stuck to the bottom of the pot. Add water and thyme, bring mixture to a boil, reduce heat to low and cook for 1 hour, stirring occasionally. The mixture should not be liquidy. Season to taste with kosher salt and freshly ground black pepper.

This recipe makes enough sauce for 2 to 3 pounds of pasta. You'll need 4 cups of the mixture above for 1 pound of pasta. Once I finished cooking the sauce, I transferred everything to large bowl, then scooped out 4 cups into a smaller, heavy-bottomed pot. Cover the remaining sauce and store in the refrigerator.

To serve, cook pasta (pappardelle pictured above) in large pot of salted water. While the pasta is cooking, warm sauce over medium-low heat, stirring occasionally. 1 minute before the pasta reaches al dente, drain and transfer to the pot with the sauce, reserving 1 cup of cooking water. Gently stir the pasta to combine with the sauce. Stir in about 1/2 cup of the cooking water to thin out the sauce, adding more if needed. Stir in 1/3 cup freshly grated Parmesan cheese.

Divide pasta amongst dinner plates and finish with extra Parmesan cheese and freshly ground black pepper.