basic vegetable stock:

put any root vegetables in a crock pot. today: unpeeled carrot, quartered yellow onion, peeled garlic, fennel stalks, celery stalks, turnips.

add herbs and other savories: peppercorns, thyme, knob of ginger and coriander and tie them up in cheesecloth.

cover with water + heat for an hour or a longer while or all day.