Beans pour boiling water and allow to cool. Drain and place in a pressure cooker, pour a little water, allow to boil, then again to cool and pour 2 liters of cold water. Add the tripe and after the pot up pressure, boil for 30 minutes. Onions, carrots and garlic are finely and fry until golden in a preheated oil. Cut the tomatoes into larger cubes, add to other products in the pan and left to stew. Add chopped into small pieces tripe. Add salt and gradually pour the broth. Add cooked beans, bay leaves and oregano and leave to simmer for about 20 minutes. Serve with chopped fresh parsley or chilli.