Put the pre-soaked beans to boil in 8 1/3 cups (2 liters) of water. Let them cook for about 15 minutes. Drain out the water and put back on the stove, but with 12 1/2 cups (3 liters) of hot water.
Allow them to boil for about an hour and 30 minutes without covering with the lid tightly. Add the cleaned and finely chopped red onions, carrots and peppers. After an hour, add the peeled and chopped tomato. Fry the flour in the hot oil, until golden in color.