In a large pot, heat 2 tablespoons of olive oil over medium heat. Add 1 ½ pounds of sliced mixed mushrooms and 2 cups of diced yellow onions. Stir frequently, cooking for about 15 minutes until the onions are translucent and mushrooms have reduced.

In a separate pan, melt 3 tablespoons of unsalted butter over low heat. Whisk in ¼ cup of all-purpose flour, followed by 4 teaspoons of sweet mild paprika, 1 tablespoon of fresh dill, kosher salt, and black pepper. Cook this mixture for 1 minute until it’s bubbly and fragrant.

Pour ½ cup of dry white wine into the pan with the roux, using a whisk to combine. Allow the mixture to simmer for about 2-3 minutes, letting the alcohol evaporate.

Gradually add 3 cups of low-sodium chicken or vegetable broth to the roux, whisking continuously until smooth. Then, stir in the reserved mushroom-onion mixture and 2 tablespoons of low-sodium soy sauce.

Stir in 1 ½ cups of whole milk and ¾ cup of sour cream into the soup, bringing it back to a gentle simmer. Cook for an additional 5 minutes, stirring occasionally.

Remove the pot from heat and add 2 tablespoons of white wine or sherry vinegar. Taste and adjust seasoning with more salt, pepper, or vinegar if desired.

Ladle the soup into warm bowls and garnish each serving with a sprinkle of fresh parsley. Consider adding a dollop of sour cream on top.