After you've used the roast chicken for a meal, drop the remaining carcass and sraps into the crockpot along with an onion or two - a couple carrots and a tsp or two of garlic.. add water to cover and cook on low overnight or all day.
Strain through a cheese cloth lined strainer - catching your broth below in a second pot catching the strained broth. discard meat and bones.
chill, remove fat
when ready to use, simply add your vegetables and cook until done, add in cooked chicken and serve.
Easy... and good!