Brush the eggplant slices on 1 side with olive oil. Heat half the oil in a large, heavy skillet over medium-high heat. Add the eggplant slices, oiled side up, and cook for 5-6 minutes until browned on 1 side. Turn the slices over, cook on the other side until browned and then transfer to a plate. Cut the slices into bite size pieces.
Heat the remaining oil in a large pan over medium heat. Add the onion, and bell peppers and cook, stirring occasionally, for 3-4 minutes uintil the onion is just softened, but not browned. Add the garlic and continue cooking for 2-3 minutes or until the onion just beginning to color.
Add the tomatoes, chili powder, cumin, and oregano. Season to taste with salt and pepper. Bring just to a boil, reduce the heat, cover, and simmer gently for 1 minutes.
Add the zucchini, eggplant pieces, and kidney beans. Stir in the water and tomato paste. Bring back to a boil, cover, and continue something for about 45 minutes or until the vegetables are tender. Take and adjust the seasoning if necessary, if you prefer a hotter dish, stir in a little more chili powder.
Ladle into warmed bowls and top with scallions and cheese.