In a large saucepan, sauté the onion, over a medium heat, until soft – about 5 minutes.
Add the stock and all but 100g of the beans and bring to the boil.
Add the chilli, tomato paste, cumin and paprika and simmer for 5 minutes.
Meanwhile, mash the remaining beans and add to the pot – keep warm.
Combine the tomato, avocado, chilli, lime juice and coriander leaves – salt and pepper to taste – set aside.
Spread a tortilla with half the bean mixture and half the tasty cheese. Dry fry in a hot pan until lightly browned underneath – place in the oven while frying the second tortilla.
Top the tortillas with the cabbage (lettuce) and salsa – dress with lime juice.