Melt butter in a 3-quart pan over medium heat. Add onion and cook for 2 minutes or until soft. Add fresh shiitake, button mushrooms, oyster mushrooms and minced ginger. Cook for 3 minutes or until mushrooms are soft and pan juices have evaporated. Stir in the cornstarch and cook for 1 minute. Stir in the vegetable broth and half-and-half. Bring to a boil, stirring constantly. Add vegetable oyster-flavored sauce and stir to mix well. Add chopped cilantro and chopped green onions. Place soup in a blender or food processor and process until smooth. Add sesame oil and pepper. Ladle soup into bowls. Garnish each serving with enoki mushrooms, green onion slivers and cilantro leaves.
Recipe courtesy of Martin Yan