Heat the oil in a large skillet over medium heat. Add the onion and carrot, cover and cook until softened, about 5 minutes.
Stir in the garlic, oregano, cumin, and saffron or turmeric and cook for 2 minutes longer.
Transfer the vegetable mixture to a lightly oiled 4 to 6 quart slow cooker. Add the tomatoes, vegetable stock, bell pepper, green beans, and chickpeas; season with salt and pepper, cover and cook on low for 6 to 8 hours.
About 10 minutes before serving, stir in the salsa, peas, olives, and cooked rice and cover.