Hungarian Mushroom Soup

Name: Hungarian Mushroom Soup
Cook time: 1 h 35 min
Total time: 1 h 35 min
Cuisine: Eastern European
Ingredients: 6 cups chicken stock; 1 ounce dried porcini or shiitake mushrooms, roughly chopped (about 1 cup); 6 tablespoons unsalted butter, divided; 1 1/2 pounds fresh cremini and/or shiitake mushrooms, sliced (about 12 cups), divided; 1 teaspoon kosher salt, divided; 1 yellow onion, chopped (about 1 1/2 cups); 3 tablespoons all-purpose flour; 2 teaspoons chopped fresh thyme leaves; 2 teaspoons Hungarian sweet paprika; 3 garlic cloves, finely chopped; 2 tablespoons Worcestershire sauce; 1/4 cup heavy cream; 1/4 cup sour cream, plus more for garnish; 2 tablespoons chopped fresh dill, plus more for garnish