Once you have a few cups or more of scraps, add them to a large stock pot and fill with water.
Boil and then simmer for about an hour. Allow to cool.
Using another large pot, strain the vegetable scraps using a cheesecloth or fabric (nut milk bag) strainer. Store in a jar(s) for up to a week in the refrigerator, or use Ziploc bags to store in the freezer.
Use as a base for any kind of soup, stew or chili.

Save your vegetable scraps (avoid cruciferous vegetables) and store them in a freezer bag (in the freezer.)

Include parts of the vegetables like:
The peelings, ends, stalks and leaves from onions, carrots, celery, cilantro, mushrooms, turmeric and ginger, and sprigs from fresh herbs.

Add a few bay leaves when ready to make the broth.