Heat a wok, add butter to it.
As the butter starts melting, add ginger-garlic to this.
Add bay leaf and saute for a minute on low flame.
Add onion and white part of the onion.
Cook till onion becomes transparent on low-medium flame.
Add vegetables of your choice.
Followed by salt as per your taste.
Fry these vegetables on medium-high flame for 2 mins.
Add water to this and bring this to boil on high flame.
Cover the lid and cook for 10-15 mins on low-medium flame. Discard a bay leaf at this stage.
After 15 mins, add the green part of spring onion and coriander leaves.
Followed by 1 tsp black pepper powder.
After 2 mins, add cornflour slurry gradually.
Stir well and boil for 5 mins on medium flame.
Add sugar to balance the flavors.
Turn the flame off. Add red chili flakes as a garnish.
Transfer soup into a bowland enjoy hot.