In a large pot, melt the butter over medium heat. Add the chopped onions and cook slowly for about 5–6 minutes until they turn soft and slightly translucent. You don’t want them browned—just gently softened.

Toss in the sliced mushrooms and stir well. Let them cook for 8–10 minutes, allowing them to release their moisture and shrink down. This step is important because it deepens the flavor of the soup.

Sprinkle in the paprika and dill. Stir gently so the spices coat the mushrooms evenly. Add the soy sauce and mix again. You’ll notice the aroma change almost instantly—warmer, richer, more inviting.

Pour in the broth and bring the mixture to a gentle simmer. Let it cook for about 10 minutes so all the flavors can blend together.

In a small bowl, whisk together the milk and flour until smooth. Slowly pour this mixture into the pot while stirring continuously to avoid lumps.

Let the soup cook for another 8–10 minutes until it thickens slightly. Stir occasionally so nothing sticks to the bottom.

Lower the heat and stir in the sour cream. Add lemon juice, salt, and black pepper. Taste and adjust seasoning as needed.

Ladle the soup into bowls and garnish with fresh parsley if you like. Serve warm with crusty bread.