Roughly chop onions and garlic. Heat oil in a deep non stick pan, add onions and garlic and sauté for 2 minutes. Add salt. Roughly chop potatoes and add. Sauté for 2 minutes.
Transfer into a mixer jar, add 1 cup water and grind to a fine puree. Pour the puree back into the pan, add milk and mix well. Add cream style sweet corn and mix well and heat. Finely chop parsley. If you wish you can add a little black pepper powder. Cook the soup till it comes to a boil.
Pour the soup into individual soup bowls, garnish with parsley and serve piping hot immediately.