1. Quarter the potato lengthwise. Place chicken breasts, carrots, and potato quarters in large skillet with lid and poach in 1/2" water for 12 minutes. Let cool enough to handle. Discard cooking liquid.

2. Trim chicken breasts. Cut chicken breasts, carrots, and potatoes into 1-inch cubes.

3. Preheat oven to 400 degrees and spray 9x13 casserole with non-stick spray.

3. In large bowl, mix cubed chicken, carrots, potatoes, drained spinach, chopped onion, and mushroom soup. Pour mixture into prepared casserole and rinse out mixing bowl.

4. Combine Bisquick, milk, eggs, and cheese in mixing bowl. Stir just until mixed, and spread mixture onto top of prepared casserole.

5. Bake 30 minutes at 400 degrees, until casserole is lightly browned. Cool for 10 minutes before serving.