Place a heavy bottom pan on the stove. Add olive oil in a cold pan.
Add chopped leeks, stir and then turn on the heat. This method is used so you don’t over heat olive oil. Overheating olive oil makes it lose flavor.
Sprinkle pinch salt on leeks to help them wilt, and sweat for a few minutes before sautéing them.
Add prepared squash and cook stirring until squash is shiny, about 30 seconds.
In a jar stir together milk and water, before pouring over the vegetable. Make sure that the vegetables are covered with the liquid, add water if not enough liquid.
Cover and cook for 30 minutes. After 30 minutes, lower the heat until the boil is down to just a simmer.
When it comes to a simmer, take some of the hot broth to dissolve miso in a bowl making sure that it becomes a smooth paste free of lumps (biting on a lump of miso would be unpleasant).
Pour the dissolved miso back into the soup, mix and simmer on very low heat for a few minutes. Don’t boil after adding miso.
Use an immersion blender or blender of choice to blend the soup imto; smooth.
Add corn to the finished soup to give it a texture.
Ladle soup into a serving bowl and garnish with chopped parsley, or scallion to serve.