Preheat oven to 350 degrees.

Using a large sauté pan over medium high heat, heat 1 tablespoon of olive oil and add the onions and sauté for a few minutes. Add the broccoli, mushrooms and garlic, and continue to cook for another 4 to 5 minutes, or until broccoli is tender. Season with salt and pepper. Remove vegetables from the pan and onto a large plate. Set aside.

In the same pan, pour in the Knorr Selects White Cheddar Broccoli Rice, the water, milk, remaining olive oil and stir together. Bring to a boil, then lower the heat to medium and boil, uncovered, for about 10 minutes, while stirring frequently until your rice is tender and the sauce is creamy. Turn off the heat and wait at least 2 minutes for the sauce to thicken.

Add the cooked vegetables back into the pan with the cooked rice and add the cooked chicken and stir together. Using a casserole baking dish, pour everything evenly into the casserole dish. Sprinkle on the cheddar cheese, evenly over the top.

Bake casserole for about 35 to 40 minutes, or until golden brown and the cheese is evenly melted and browned. Serve and enjoy!