In a non-stick skillet over medium heat, brown the ground chicken and the onion until the chicken is no longer pink.
Stir in pepper, water and mushroom soup and heat till bubbling.
Add frozen vegetables and stir cook until the vegetables are warm.
Pour the mixture into a 2 quart (2L) casserole. Arrange tater gems in a single layer on top of the chicken mixture. Bake, uncovered, for 40 to 45 minutes or until the tater gems are crisp and the chicken mixture is bubbling.