Combine your broth ingredients in a crockpot (or a regular pot, if you must). Cover with water. Leave stewing for 12-48 hours, depending on your ingredients--shorter for vegetables and chicken or lamb, longer for beef or bison. Check periodically to make sure water level stays above the bones/veggies.
Once it is time, use a mesh strainer lined with cheesecloth to strain. I have a HUGE problem with finding small bits of bone in my soup (it makes me not want to eat it) so I strain it and then add the chunks of marrow back in.
Dice onions, carrots, and zucchini. Combine all of the onions, half of the carrots, spinach, half of the peas, and half of the zucchini in a pan and fry over medium heat with a little bit of oil or butter until soft.
Remove from heat and transfer to blender with a small amount of water. Add raw garlic and blend until smooth. Adding some winter squash here is great too, I tried pumpkin last week and it was wonderful.
Combine your puree and bone broth in a large pot and stir. Toss in your herbs and spices and the remaining vegetables. If you want to add cauliflower, meat, or anything else to give the soup some texture feel free to get creative! Cover and place over low heat for around an hour to let the flavors properly combine.