I sear my ground beef/pork mix on medium-hihh, then remove it from the pot. I cook diced onion in the grease, then add diced carrot and celery. After they all soften, I mix in tomato paste and let it sear too, but not super long, like 3 minutes max. I deglaze with a cup of white wine (I like using Riesling, but it works with dry wines too), and let the alcohol cook out a little bit, 5 minutes or so. Then I remove from heat, re-introduce the meat and stir, then cover with beef broth, give it another good stir, and add a cup of milk and some shakes of nutmeg. Bake for 3 hours at 375-390 (depends on how much liquid vs char you like), then add pasta, a cup of heavy cream, a hefty scrape'n'stir, and parmesan flakes on top.
Use an oven-safe pot! Also, spice your meat as preferred, I have my own ratio of garlic powder, onion powder, and S&P that I like for ground meats. I find that adding things like oregano, basil, etc take away from the taste of this sauce, but they're not bad by any means.
It's Wild Style or something like that. Like S2E2 or 3, I just watched it the other day