Peel the prawns. Add the scales to a large pan together with the peeled garlic, chopped tomatoes, dried chili, lemongrass (optional), some olive oil and a pinch of salt.

Place the pan over medium heat and fry the ingredients for 4 minutes. Then add the tomato juice, tomato paste, the stems of the cilantro and 2 cups (480 ml) of water.

Turn the heat higher until the ingredients start to boil. Then lower the heat again and cover the pan. Cook the tomatoes for 15 minutes. Then take the pan off the heat. Let the soup cool down for 10 minutes. Remove the lemongrass because it's too tough. Blend or mix the soup.

Then strain it. Discard the tomato pulp. Keep the tomato soup aside until later. Add the chopped onion and carrot and some olive oil to a pan.

Then place the pan over medium heat and fry the vegetables for 5 minutes until the onion is glossy. Then add the diced celery and peeled prawns. Season with a pinch of salt.

Stir and cook the vegetables and prawns for 2 more minutes until the prawns are cooked. Then add the tomato soup.

Turn up the heat until the soup starts boil. Cook for 3 minutes. Turn the heat off again. Pour in the lime juice. Add the chopped cilantro. Check the seasoning. Add salt, pepper or lemon juice to taste. Scoop the soup into bowls. Then sprinkle with chopped avocado and extra cilantro. Serve hot.