I am using Hazan's recipe from her Essential of Classic Italian Cooking. This is a great book to have (unless you already own a copy of her iconic, The Classic Italian Cook Book: The Art of Italian Cooking and the Italian Art of Eating). The recipe, actually, is available online.

I started with this recipe and over the years I have modified it to perfect it to my standards.

Here're my modifications and suggestions.

First, do not question the choice of meat: you want ground chuck. Any meat that is leaner of fattier simply won't do it.

Use beef only (ie, do not replace part of it with ground pork) but *add* 0.5-1 lbs of dry prosciutto. Dry prosciutto is easy to make. You buy regular prosciutto, then throw the slices on a aluminum foil lined cookie tray, broil them until crispy (4-6 minutes), and crumble them to small pieces. You add the prosciutto after the whole milk step in the recipe.

I replace the nutmeg with 1/4 teaspoon of cinnamon and 1/8 teaspoon of cumin. The recipe can tolerate a bit more cinnamon (up to 1/2 teaspoon), if you like the flavor. You can still include the nutmet, in addition to cinnamom -- if so, exlude the cummin.

I add two cloves of garlic, finely chopped. I add it along with the carrots and the celery. The recipe can tolerate couple more cloves as well.

At the end of the recipe I add 1-4 whole dried red chili peppers (depending on the heat tolerance of our guests). I add these peppers whole and often in a bouquet garni (ie tied up in cheese cloth so that I can easily retrieve and discard them after cooking).

And now for the kill: instead of the canned tomatoes I get 2 lbs of fresh campari tomatos (Costco has them year round, otherwise roma tomatoes would do as well). I place them whole on an baking tray lined with aluminum foil, drizzle them with a bit of olive oil (1/8 of teaspoon per tomato), and roast them in preheated 400F over for 2-3 hours -- until dark-red with black highlights, wrinkly, and reduced to 1/2-3/4 of their original size. Then I mash them in a bowl using a fork and I use this roasted tomato "puree" in my sauce. (Instead of mashing them you can also give them a quick turn in a food processor: 3 jolts, each 4-5 seconds, ought to do it. You want them chopped in irregular pieces, not completely pureed).

I let the sauce simmer at the lowest setting for at least 7 hours. Simmering should produce a few bubbles here and there but no more.

Notice that the roasted tomatoes turn very sweet and consequently will increase the sweetness of the recipe. That's ok -- the saltiness of the dry prosciutto will balance things!

Because of the long simmering, and the time it takes to roast the tomatos, it usually takes two days to prepare the sauce. On day-one I roast the tomatoes and on-day two I complete the recipe.