Heat oil in a large pot over medium-high heat then add the onions and bell peppers and cook until soft and beginning to brown, about 5 minutes. Add the ground beef and stew meat and cook for 5-8 minutes, stirring the meat occasionally to cook through.
Add the cumin, chili powder, paprika, garlic powder, salt, pepper and cayenne pepper and stir together until all of the meat is coated in the spices. Cook for 2 minutes, until the meat is very thick from the spices.
Add the kidney beans (with liquid from the beans), diced and crushed tomatoes and bring the chili to a boil. Lower the heat to medium-low, cover the pot and simmer the chili for 30 minutes.