Heat a little oil in a large saucepan or casserole dish over a medium heat.
Add the onion and cook for about 5 minutes until softened.
Stir in the garlic and cook for 1 minute, then add the carrot and red pepper. Cook for a further 3 minutes, stirring occasionally.
Add the tomato purée, chipotle paste, cumin, oregano and smoked paprika. Stir for 1 minute until the vegetables are coated in the spices.
Add the potatoes and stir well to coat them in the tomato and spice mixture.
Pour in the chopped tomatoes and enough vegetable stock to cover the vegetables generously.
Bring to the boil, then reduce the heat and simmer for about 15 minutes, or until the potatoes are almost tender.
Stir in the black beans and green beans. Continue cooking for 5 minutes, or until the beans are heated through and the vegetables are tender.
Taste and adjust the seasoning if needed.
Serve topped with chopped parsley or coriander and a squeeze of lime juice.
For a richer finish, serve with a spoonful of sour cream if dairy is suitable for your diet.