Cheesy Chicken, Broccoli & Rice Casserole

In a large bowl, whisk together cream sauce base, stock concentrates, mustard, cream cheese, three-quarters of the garlic powder, 1⅓ cups water, and 1 tsp salt until mostly smooth (2⅔ cups water and 2 tsp salt for 8 servings). Transfer mixture to prepared baking dish. Add rice, broccoli, and half the cheddar; stir to combine.

Pat chicken dry with paper towels and season all over with salt and pepper. Arrange chicken in a single layer over rice mixture. Cover baking dish tightly with foil, then place on top of a baking sheet. (Placing a baking sheet under the dish will help protect against any of that deliciousness bubbling over into your oven as it bakes.) Bake on middle rack until chicken is cooked through and rice is tender, 45 minutes (60 minutes for 8 servings).

While casserole bakes, place 2 TBSP butter (4 TBSP for 8 servings) in a medium microwave-safe bowl. Microwave in 10-second intervals until melted. Add panko, remaining cheddar, remaining garlic powder, and a big pinch of salt and pepper to bowl; stir to combine.

Once casserole has baked 45 minutes (60 minutes for 8 servings), carefully remove foil. Transfer baked chicken to a cutting board. Using 2 forks, shred chicken into bite-size pieces. Return shredded chicken to casserole, then add 2 TBSP butter (4 TBSP for 8); stir to combine. Taste and season with salt and pepper if desired.