Brown the burger and onions together.
Drain off the fat and transfer to an 8-quart pan.
Add juice, beans, and chili powder to the pot. Bring to a boil, then turn down and simmer for at least an hour. If using a slow cooker, cook on the low heat setting for 8 to 10 hours or on the high heat setting for 4 to 5 hours
If using a slow cooker, cook on the low heat setting for 8 to 10 hours or on the high heat setting for 4 to 5 hours