Start by washing and slicing the mushrooms, then finely chop the onion. In a large soup pot over medium heat, melt the butter and sauté the onions for 3-4 minutes until translucent. Add the mushrooms and cook for 7-10 minutes, stirring occasionally, until they release their juices. The aroma will be rich and earthy—this step lays the foundation for your soup’s depth of flavor.
Sprinkle in the sweet paprika and stir well to coat the mushrooms and onions evenly. This gives the soup its signature smoky-sweet Hungarian taste. Next, add flour and cook for 1-2 minutes, stirring constantly to remove the raw taste. Slowly whisk in the vegetable or chicken stock to form a smooth base, then bring it to a gentle simmer.
Reduce the heat to low and slowly stir in the milk and heavy cream. Doing this gradually helps achieve a silky, velvety texture. This rich, creamy base elevates the mushroom flavor to a whole new level.
Stir in the soy sauce, salt, and freshly cracked black pepper. For a touch of brightness, you can also add a splash of lemon juice. Let the soup simmer gently on low heat for 10-15 minutes, stirring occasionally. This allows the flavors to develop and the broth to thicken beautifully.
Add chopped fresh dill into the pot, saving a little for garnish. Dill adds a fresh, aromatic lift that balances the creamy richness. Ladle the soup into bowls, top with a dollop of sour cream if desired, and garnish with a sprig of dill. Serve with crusty bread for the ultimate cozy meal.