Brown the ground beef using the sautee mode on your slow cooker.
Switch to slow cooker mode on high. Add crushed tomatoes, 1 cup bone broth, sweet potato, chili powder, pumpkin spice, salt and pepper to the slow cooker with the ground beef.
Slow cook for about an hour or until sweet potatoes are softened.
Add in red bell pepper and onion. Continue to slow cook 30 minutes to an hour. If continued slow cooking is desired, switch over to "low" or "keep warm" mode on your slow cooker. Add extra 1 cup of bone broth if needed to create desired thickness.
Serve with optional toppings.
Stove stop instructions: Use a large pot of medium heat to brown the meat. Add the rest of the ingredients and bring to a boil. Once it begins to boil, reduce heat to simmer and cover. I would allow it to simmer for at least an hour.