I usually just throw in whatever veggies we have in the fridge along with carrots and celery [which i hate. ew] This batch had 1 giant onion, potatoes, and italian parsley. I also freeze the leftover rinds from cheese and add those as well.
I season with salt and pepper, rosemary, bay leaves and thyme.
really what it comes down to is patiently waiting, which is hard to do when your entire house smells like hot deliciousness.
[the parts I pick out]