Photo of Chicken, mushroom, and brown rice slow cooker casserole by WW

Chicken, mushroom, and brown rice slow cooker casserole

Total Time
7 hr 21 min
15 min
7 hr 6 min
A fabulous slow cooker meal that’s easy enough for a casual weeknight meal and tasty enough for a weekend gathering. You can keep the prep time to about 15 minutes if you brown the chicken while you prep the veggies. Then assemble the everything in the slow cooker and allow it to take care of the rest of the cooking for you. We recommend not skipping the step of browning the chicken because it adds so much more flavor to the casserole. While this recipe calls for cooking the chicken in a separate skillet, there are slow cookers on the market that have inserts that can go right from the stovetop to the cooker — and that means there’s one less pan to clean up.


Cooking spray

2 spray(s)

Uncooked skinless boneless chicken thigh

20 oz, use eight 2 1/2 oz thighs

Chicken broth

2 cup(s), reduced-sodium

Cremini mushroom

½ pound(s), sliced

Uncooked leeks

1 cup(s), white and pale green parts only, thinly sliced, washed carefully for grit


1 cup(s), thinly sliced


1 cup(s), chopped, thinly sliced

Uncooked long grain brown rice

¾ cup(s), medium-grain (such as brown Arborio)

Worcestershire sauce

2 tsp

Dijon mustard

1 tsp

Dried sage

1 tsp

Table salt

1 tsp

Black pepper

½ tsp, freshly ground


  1. Coat a large nonstick skillet with cooking spray; warm over medium heat. Add the chicken thighs and brown, turning once, about 6 minutes; set aside.
  2. Combine the remaining ingredients in a 5- to 6-quart slow cooker; nestle the chicken thighs in the mixture. Cover and cook on low for 7 hours. Yields 1 chicken thigh and about 2/3 cup rice-vegetable mixture per serving.