Peel and finely dice the onions and garlic. Wash and clean the tomatoes and cut them into large pieces. Heat the oil in a pot. Sauté onions, garlic and tomatoes in it. Add 1.5 litres of cold water, stir in the contents of the bag and bring to the boil.
Put the beans in a sieve and rinse. Drain the corn. Add both to the soup and simmer for about 5 minutes, stirring from time to time. Grate cheese. Spread the chips on a baking tray lined with baking paper.
Sprinkle cheese over it. Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) until the cheese has melted. Season soup with coriander, salt, pepper and 1 pinch of sugar.
Garnish with coriander leaves. Add cheese chips.