Miso, a traditional Japanese seasoning made from fermented soybeans, adds a unique umami flavor to this mushroom soup. The earthy and meaty mushrooms are sautéed with garlic and ginger, then simmered in a broth made with miso paste and vegetable stock. The result is a savory and comforting soup that is both satisfying and nourishing. Garnish it with sliced green onions and a drizzle of sesame oil for extra flavor.