Pork shoulder is one of my favorite cuts. It's so forgiving, so succulent, and it lends itself to such a wide array of preparations, whether you marry the meat with barbecue sauce or a spice-rub and slow-roast it for sandwiches or tuck it into tacos. Basically, so long as you cook that pork to tender submission, you can't go wrong, and the slow cooker is the perfect tool to get it there.
For this simple, soul-soothing version, I sautéed fennel, carrots, and onions until they're lightly caramelized and tender, and I built the sauce from there, adding white wine for acidity, a dash of Worcestershire for backbone, and a variety of dried Italian herbs that meld into a tomato-based sauce that braises the meat for a lengthy 10 hours in the slow cooker. The addition of a Parmesan rind, which gets discarded later, provides rich complexity. The key to tying the dish together is bathing the meat in the liquid occasionally; this way, the pork stays moist and the flavors properly mingle. It's not an exact science, though, so don't sweat it. Skip an hour here or there (or even let it go while you're at work) and it'll still turn out fine.
When the meat reaches the point that it's fall-apart tender, remove it from the liquid and skim the fat from the top of the sauce. Or you can place it all in the refrigerator, storing the pork in the liquid, and reheat it later. Doing so makes skimming it later easy since the grease solidifies on top. Regardless, you'll want to let the meat cool before pulling it or shredding it using two forks. Discard the bone and excess fat and serve it piled on top of pasta, finishing the dish with a shower of shredded Parmesan cheese.