Heat the olive oil in a large pot over medium heat. Add the onion, salt, and several grinds of pepper and cook, stirring occasionally, for 8 minutes, or until softened. Add the carrot and sweet potato, stir, and cook for 2 more minutes. Add the canned tomatoes, garlic, oregano, and red pepper flakes. Stir in the broth and bay leaves. Bring to a boil, then reduce the heat to a simmer and cook, covered, for 20 minutes. Stir in the cherry tomatoes, green beans, zucchini, and chickpeas. Cover and cook for 10 to 15 more minutes, or until the green beans are tender. Stir in the vinegar and the kale and cook for 5 minutes, or until the kale is wilted. Season to taste with salt and pepper and serve.