Put all of the ingredients, except the tapioca flour, into the slow cooker. Mix everything together.
Mix the 2 tbsp of tapioca flour into a small amount of water. Pour that water into the crockpot and mix well.
Cook on high for 5-6 hours.
When it's done, let it cool down (broth will thicken as it cools). If you need a little extra help thickening it, add 1 tbsp of tapioca flour into a small amount of water and mix that into the broth.
Serve over mashed potatoes for extra delicious-ness! Enjoy!