Lay frozen thighs inside pot and pour 1 cup of your sauce of choice over the top. Close lid and cook on low for 6 hours.
If yours are in one solid chunk, break apart the pieces after hour 3 or 4 so the meat can break down easier.
Continue cooking until 20 minutes before serving. Then use two forks to shred meat. Leave in pot, pour last 1/2 cup of sauce into pot. Stir to coat meat. Allow to continue sitting and cooking in sauce for last 15-20 minutes. Then serve.