Ask ten Italian cooks for their Bolognese recipes, and you will get ten different recipes. Similar, but different. Some add milk, some don't. Some use a combination of meats, some use only beef. It goes on and on. I've made a lot of meat sauces, but this is my favorite. I have to say, though, I really don't measure anything, so it's a little different every time. But that's the fun of it. The basic technique is the same, though. You begin with a soffritto (aromatic vegetables), cook that until it's soft, add your meat, then add some wine, let that cook off, add your tomato and broth and seasonings. Let all that cook low and slow for a very, very long time. This is the basic recipe.
In a heavy pot, brown the meats. Remove the meat, drain the fat. Do not wipe the pot.
In the same pot, add some olive oil and add the onion, carrot, celery. Let that cook slowly, for about 10 minutes. Add the garlic and cook for a couple of minutes. Add your meat back in. Turn up the heat a little. Add the red wine and let the liquid cook off. Add the beef broth and then the tomatoes and herbs. Turn the heat to low and let this simmer, uncovered for at least a couple of hours. The longer the better. If it gets too dry, just add a half cup of water and keep cooking, letting the liquid cook off. Taste and salt and pepper as you like it.
Serve over pasta.
Yes, I grind my own meat. I know exactly what's in it that way. The KitchenAid grinder attachment works great. I couldn't do a lot of things without that KitchenAid mixer. It's a wonder. This is the one I have and I love it.