1Heat 1 tablespoon oil in a large saucepan over medium heat.
Add the chopped onion (100g) and sauté for 2-3 minutes until translucent.
Add the diced carrot (70g) and potato (150g), and cook for another 3-4 minutes, stirring occasionally.
Add the chopped tomatoes (240g) and finely chopped green chilli (10g). Sauté for 2 minutes until the tomatoes soften.
Pour in 1 liter of water and bring the mixture to a boil.
Lower the heat and simmer for 15-20 minutes, until the vegetables are tender.
Add 1 tablespoon tomato ketchup, 1 teaspoon oregano, and salt to taste. Stir well and simmer for another 2 minutes.
Turn off the heat. Add 1 tablespoon lemon juice and 1 tablespoon chopped coriander. Mix well.
Serve the hot & tangy vegetable soup immediately, garnished with extra coriander if desired.