Can I tell you a secret? You have to promise you won't tell anyone...
Alright, if you promise you won't tell, I'll tell you my secret. Are you ready for it? Well, here it is.
I only pretend that I make homemade stock for culinary reasons. Any talk of "oh, there's just no comparison" or "it really is worth the extra effort" is just that - talk. Sure, it may all be true, but it's not the reason I make stocks. In fact, I regularly buy boxes of the stuff and use it frequently (the six-pack from Costco and I are besties).
Nope. I make homemade stock because I'm kind of cheap and hate wasting things. And homemade stock is a great way to clean out the veggie crisper. It's just a bonus that it's super easy and makes my house smell good. In fact, it's so easy that it just may change your life.
Here's what I do:
If you want to make a meat stock, save the bones (a chicken carcass works really great). Put that at the bottom of a crock pot (mine is a 4-quart, and I think a slightly larger one would work better, but I make do). If you want to do a veggie stock, skip this step.
Next, add some veggies. I think onions, carrots, and celery are the essentials, but I've not used carrots or celery when I was out. Baby carrots, shredded carrot, carrot coins - whatever you've got. If you're using whole carrots, you don't even need to peel them. Cut those and the celery into big chunks. If you have a whole onion, chop it into big chunks and leave the skin on. The skin will help the stock get a nice dark color. If you have something else onion-y that you want to get rid of, throw that in too - shallots, scallions, leeks... they're all good. I'm pretty sure I added a green pepper once when I discovered I had one that was at the "I need to use this by tomorrow or throw it out" stage.
Add some garlic. I prefer to use whole cloves, in their skins (again, the skins help get that nice stock-y color), but if you only have a jar of minced or those little frozen garlic cubes from Trader Joe's, throw a few cloves worth in.
Next add some fresh herbs - a few full sprigs. I prefer to use Parsley and Thyme, but I'm really not picky. I've used Rosemary instead. Once, I even threw in some arugula. Use whatever you've got. I wouldn't recommend using dried herbs, though - only fresh, whole sprigs.
Throw in a palm full of whole peppercorns.
Cover everything with water, put the lid on the crockpot, and cook on low for 8-10 hours.
Pour everything through a fine mesh strainer and let cool before packaging up into individual containers. It will stay in the fridge for a few days or frozen for a long time.