I have a bag in the freezer dedicated to veggie leftovers. This includes the ends of carrots, zucchini, the core of your bell pepper, the outside of the onion, extra kale, spinach that I’m not going to use before it goes bad, stalks of broccoli. Avoid bitter vegetables like arugula or brussel sprouts. Once your bag is full, you can make some broth.
There are two versions of broth, basic veggie or bone broth. Bone broth is more nutrient dense and obviously requires bones. The basic version is faster and easier. It doesn’t have the same nutritious value but it is vegetarian friendly and cheaper.
Veggie broth: Throw all those veggies you’ve been saving into a crock-pot and cover with water. Top with any fresh herbs you have lying around (basil, oregano, etc. nothing too powerful like mint), a bay leaf and black pepper corns if you have some on hand. Set the crock-pot on low and cook while you are at work or overnight (try for at least 8 hours). I use a spaghetti server to scoop out as many of the big vegetables as possible. Once the big items are in the trash, pour the broth through a strainer into a clean container. I like to use a large glass measuring cup. Pour the broth into mason jars, seal, let cool and then place in fridge until use.
Bone Broth: Add all your freezer veggies, plus bones of high quality meat into a crock-pot. Add 2 TBS of apple cider vinegar and fill with water. The apple cider vinegar helps pull the nutrients from the bones as it cooks. Add in fresh herbs, bay leaf, and black pepper corn. Cook on low for 18-24 hours. Use the same process as the veggie broth to strain and save the bone broth. The bone broth will be much darker than your veggie broth.
All broth color may be different depending on what vegetables and bones you use. You can make broth on the stove top but I find it’s easier to turn on the crock-pot and leave it.