In the bowl of your slow cooker, combine the rice, chicken, carrots, celery, shallots, broth, thyme, sage, crushed red pepper, and a pinch each of salt and pepper. Add 1/2 cup water. Cover and cook on low for 5-6 hours or on high for 2-3 hours.: The slow cooker stage is where flavors marry gently, producing a broth that tastes developed without much hands on time. As the pot warms you will notice the broth steam and carry an inviting, herbaceous perfume, with faint sweetness from the carrots and a savory backbone from the chicken . I like to check the rice around the lower end of the timing to prevent mushiness, because different rice blends vary in absorption. A common mistake is leaving the lid off early to peek, which lengthens cooking and cools the pot, so lift minimally. If you worry about overcooked wild rice blend , try the high setting for a shorter window, then adjust next time once you know how your cooker behaves.
Shred the chicken with 2 forks. Stir in the cream, parmesan, and spinach. Cook until warmed through, about 30 minutes. Stir in the parsley. If the soup is thick, add an additional 1/2 cup water.: As you shred the chicken , you'll feel how tender it becomes after slow cooking, and the strands soak up the broth, dispersing flavor throughout the bowl. When you add the cream and parmesan , expect the aroma to shift to a richer, slightly sweet dairy note, and the surface will develop a gentle gloss. Adding the spinach late preserves its bright color and tender texture, and the chopped parsley freshens the final mouthfuls. If the pot thickens—often because the wild rice blend absorbed a lot of liquid—stir in hot water or extra broth gradually until you reach a spoonable consistency. Avoid overheating after dairy is added, as a furious simmer can break the emulsion and change the texture.
To make the mushrooms. Preheat the oven to 425 degrees F. On a baking sheet, combine the butter, mushrooms, garlic, rosemary, lemon zest, and a pinch each of salt and pepper. Transfer to the oven and roast for 25-30 minutes, stirring halfway through cooking, until the mushrooms are golden and crisp.: Roasting at high heat concentrates the mushrooms' flavor, and you will see edges darken and juices caramelize into sticky, savory pockets. The butter and smashed garlic brown and perfume the pan, releasing an addictive aroma that contrasts with the gentle soup steam. Stirring midway exposes more surfaces to direct heat, ensuring even browning and preventing soggy bottoms. A pitfall is overcrowding the pan, which traps steam and prevents caramelization, so spread the mushrooms in a single layer. Remove the rosemary stems before serving for a clean texture and to avoid biting into a woody twig.
