Slow Cooker Mushroom and Wild Rice Soup

Preparation

1. Step 1

   Put the butter in a microwave-safe container (a liquid measuring cup works well) and microwave until the butter is completely melted, 30 seconds to 1 minute. With a fork, whisk the flour into the butter to make a smooth mixture the texture of cake batter, then microwave until the roux is steaming hot and bubbling slightly around the edges, about 30 seconds.

2. Step 2

   Scrape the roux into a 6- to 8-quart slow cooker and whisk in the stock and wine. Stir in the mushrooms, wild rice, celery, onion, carrot, chopped garlic, thyme and garlic powder. Season with 1 teaspoon salt and several generous grinds of black pepper. Cook on high until most of the rice grains are just slightly split open and the vegetables are tender, about 4 hours. (The soup can hold for 1 to 2 hours on the warm setting, but eventually the wild rice will overcook.)

3. Step 3

   Turn the heat to warm. Put the sour cream in a small bowl and slowly whisk in a few spoonfuls of the hot soup until smooth, then stir the mixture into the soup. (This prevents the sour cream from separating.) If you’d like the soup to be thinner, whisk in warm broth or water to the desired consistency. Taste the soup and add more salt and pepper to taste.

4. Step 4

   Divide the soup among bowls and top with chopped scallions or chives and dill. Reheat any leftovers on low until warm. (Boiling can cause the sour cream to break.)