Clint here:
I have found an easy way to make delicious, home-made vegetable stock, while doing my part to decrease food waste.
Every time I cut up vegetables such as carrots, onions, celery and seed tomatoes, I end up with the stem ends of the plant that I used to throw in the trash. Now I save these odds and ends and throw them into a large ziplock bag that I keep in the freezer. This is also a great use for celery that has gone limp, or any other veggies that might be a bit old, but not rotting.
Now when I need stock for a soup base, (or when the bag is getting full), I just take it out of the freezer, pull out some veggies, and put them in a pot, (or crockpot), and simmer for a couple of hours and voila, I have delicious stock with almost no effort! I have also made chicken stock using the bone carcass of a chicken and add some of my veggies from my freezer bag to make awesome chicken stock.
After the stock has finished simmering, strain the liquid through a sieve, or colander, but instead of throwing the vegetables in the trash, take them out to your compost and throw them in.
I get such a sense of satisfaction by using every part of the plant and making wonderful stock in the bargain. I hope you do too.