- 2 cups low-fat milk
- 8 cups vegetable stock
- 1 1/4 cups unbleached wheat flour
- 1 teaspoon salt
- 1/4 cup dill weed
- 1/4 cup paprika
- 1 1/2 teaspoons black pepper
- 1 cup (2 sticks) unsalted butter
- 2 1/2 yellow onions, diced
- 1 1/2 cups sour cream
- 3 pounds crimini mushrooms, sliced
Heat milk and vegetable stock over low heat. Set aside.
In a bowl, whisk together flour, salt, dill, paprika and pepper, making sure to break up any paprika lumps.
In large soup pot, melt butter over low heat. Raise heat to medium and sauté onions until translucent, 8 to 10 minutes.
Reduce heat to low. Add flour mixture to the soup pot and stir well. Cook for 5 to 8 minutes, stirring constantly, to activate the roux.
Add hot milk-vegetable stock mixture in increments to the soup pot, each time stirring until smooth and allowing the temperature to rise to a simmer. Simmer soup over medium heat until roux “blooms” by changing color and texture, 20 to 30 minutes.
Place sour cream in previously used mixing bowl. Pour 2 cups hot soup into sour cream to temper; whisk until smooth. Reserve.
Add sliced mushrooms to the pot, stir well, and simmer about 5 minutes; remove from the heat. At first it will seem as though there are too many mushrooms relative to the size of the batch of soup, but don’t skimp on the mushrooms!
Stir in tempered sour cream.
Reheat soup in a double boiler to just 165° F. Overheating will cause it to break and become oily.