Step 1

Preheat oven to 400 degrees F (200 degrees C). Lightly grease a 9x13 inch baking dish.

Step 2

Heat the olive oil in a skillet over medium heat, and cook the chicken 5 minutes on each side, until juices run clear. Remove from heat, and slice into strips.

Step 3

Bring the water to a boil in a saucepan. Place sprouts in the pan, cover, and cook 10 minutes, until tender.

Step 4

Arrange sprouts in the prepared baking dish. Place mushrooms over the sprouts, and sprinkle with 1 cup Swiss cheese. Layer chicken over cheese. In a bowl, mix the half-and-half, milk, garlic, and remaining Swiss cheese. Pour over the chicken. Season with pepper and garlic salt.

Step 5

Cover, and bake 35 minutes in the preheated oven. Reduce heat to 350 degrees F (175 degrees C). Uncover casserole, and continue baking 20 minutes, until bubbly and lightly browned. Sprinkle with Parmesan cheese to serve.