How I Make Bean Soup:
Prep time: Couple of days, but worth it.
Start with several smoked ham hocks in the crockpot: at least two or three, four if they’ll fit. Toss in a couple of bay leaves and about a tablespoon of peppercorns. Add however many cans of chicken broth will fit (usually three–you want enough to mostly cover the hocks) and cook several hours, or until the hocks are falling apart. Throw the entire thing into the fridge to cool off overnight.
When chilled the next day, use utensil of your choice to remove and discard what fat has collected and solidified on top of the soup (there will be plenty due to the hocks). Begin to reheat the soup until it melts (good hocks will gelatinize the broth). When it is liquid again, remove the hocks and strain the broth, returning the broth to the pot. Toss the bay leaves, and crush the now softened peppercorns, returning them to the pot. Sort through the hocks and pick out the meat, chopping it and returning it to the pot. Toss the scraps in the yard for the crows. 
Pick through and rinse about 1 1/2 cups of dry mixed beans and add them to the soup. Add about 3/4 cup of pearled barley. Add whatever herbs strike your fancy. Toss in some chopped veggies–I use a few carrots sliced, a few celery stalks chopped, a medium white onion chopped, possibly a green bell pepper chopped if I have one, and (I know, it’s weird, but it’s good) a drained can of sliced water chestnuts. Oh, and garlic. Can’t forget about the garlic. Several smashed cloves are good. Cook this for hours (I usually cook on low for at least 12-15 hours 'cause I’m a freak).
Cook this long enough, and the starch in the beans and barley will cook out into the broth and thicken it beautifully; but you can always toss in the roux that Fear Itself mentioned.
You can throw the vegetables in more towards the end of the cooking time if you want some texture left in them. Myself, I shoot for pure flavor, so I cook them to death.
More meat can be added, as well, if the hocks don’t provide as much as you’d like. Chopped ham or smoked sausage work well, but I’ve been known to open the stray can of SPAM for this when I needed it.
Of course, the final step in preparation would be to again refrigerate this for a day or two, just to give everything a chance to mingle and mature. The final result when cold is comparable to peanut butter in viscosity, and when reheated, only slightly less so.
Full of smokey hammy goodness, though.