Add the oil to a large skillet over medium-high heat. Add the beef (or bison) and brown, breaking up the clumps with a wooden spoon. Drain off fat (I didn't my meat was grass fed and not very fatty).
Add the chili powder, cumin seeds, oregano and cinnamon. Cook for a couple of minutes, stirring to combine. Then add the water, tomato paste, and vinegar, stir and then spoon out into the slow cooker.
Add the onions, peppers, corn, green olives, garlic, tomatoes with their juice, and salt and pepper.