Chicken & Broccoli Casserole

Preheat oven to 400 degrees F.

Heat oil in a large ovenproof skillet over high heat. Add chicken and cook until well browned, about 4 minutes per side. Transfer to a clean cutting board and let stand for 5 minutes. Cut into 1-inch cubes.

Whisk flour and 2/3 cup milk in a small bowl. Add the remaining 3 1/3 cups milk to the pan; bring to a boil over medium-high heat. Gradually whisk in the flour-milk mixture. Return to a boil and cook, stirring often, until thickened, 2 to 3 minutes. Stir in rice and broccoli; return to a boil and cook until the broccoli is tender, about 2 minutes. Stir in the chicken, cheese, salt and pepper. Sprinkle onions on top.

Transfer the pan to the oven. Bake until the casserole is browned and bubbling, 10 to 12 minutes. Let cool for 5 minutes before serving.