In a large sauté pan, heat the olive oil over medium-high heat until just smoking.

Add the green and red peppers, onion, and garlic and sauté for about 5 minutes, until the peppers are softened. Add the chili powder, cumin, and cayenne pepper and sauté for 1 minute. Add the zucchini, squash, crushed tomatoes, and water.

Cover and turn the heat down to medium. Cook for about 20 minutes, stirring once or twice. Uncover, stir in the kidney beans, and cook until heated through.

Top each serving with grated cheese.