This might be the most flavorful mushroom soup I’ve ever made. The deep earthy flavor comes from the mushroom broth, with a natural sweetness added by leeks and herbs. A splash of cream introduces a layer of richness. This combination, along with the savory umami taste that mushrooms naturally possess, creates a soup that’s rich in flavor and deeply satisfying. Umami is often described as the fifth basic taste, characterized by a rich and savory flavor that deepens the overall taste experience in foods like broths, meats, and certain vegetables.