Heat oil, add onion, leek, and celery, and saute for about three minutes, add minced garlic and saute for a few more seconds.
Add water, tapioca, vegetable powder, curry powder, salt, and pepper, and stir.
Add the corn, stir and bring to a boil; lower the heat and cook for 10 minutes; add coconut milk and stir; if too thick, add water gradually; Cook for another five minutes. Taste and adjust seasoning if necessary.
Remove from heat, if desired, and set aside a cup of boiled corn kernel for garnishing; Grind the soup in a pot with a stick blender.