In a pressure cooker / pan, heat 1 tsp of oil. Throw in the garlic cloves. After a few seconds, transfer in all chopped vegetables along with dried basil and chopped green chilli.
Saute this mix for a minute or so. Add 2 cups water and a tsp of salt. Pressure cook for 3-4 whistles and then keep the flame on Sim for 3-4 minutes. Idea is, to cook it to a mush. (In case you don't have a pressure cooker, you can microwave this or boil it for 30-45 minutes to achieve the mushed up consistency).
Once the cooker has cooled, drain the contents through a colander. Reserve the liquid. Put in the vegetable mush into a blender with some water to make a very fine puree.
Empty the puree into a saucepan, add the reserved liquid and remaining 2 cups of water. Bring to a boil.
Dissolve the flour used in a few tbsp of fresh water and pour it into the boiling soup to thicken it further.
After simmering for a couple of minutes, remove the saucepan from heat. Check for salt. Season with some freshly ground black pepper and garnish with fresh basil leaves from your kitchen garden. I did my first little basil harvest for this soup. It is a wonderful feeling.