1. In a small bowl mix corn flour with 3 tablespoons water till smooth. Set aside.
2. In a large pan or pot bring the rest of the water to boil. Put in the carrots and cook for 3 minutes. Add the French beans and cauliflower. Stir and cook for a few more minutes. Put in the cream style corn and mix well. Add the corn kernels in the end and cook for another 5 minutes.
3. Season with sugar, salt and pepper to taste and continue to cook for another 3 minutes. Pour the corn flour mixture and stir well to incorporate. Cook for another 5 minutes or till the soup thickens to desired consistency. Put in the spring onions and let it cook for another 2 minutes. Turn off the heat.
4. In a serving bowl, serve the soup hot garnished with coriander leaves.