Combine yogurt, flour, and garlic powder together in a mixing bowl. Knead by hand until the dough forms a ball. Roll out onto floured surface into a flat circle for the top of your pot pie. Mine was definitely not a perfect circle.
In a mixing bowl, combined cubed chicken, cream of mushroom soup, frozen veggies, and 1/4 cup water.
Spray casserole dish with non-stick cooking spray. Add chicken mixture. Top with dough. Bake at 375*F for about 30 minutes or until crust is no longer doughy in the center, checking after 20 minutes to make sure it's not going to burn. My oven seems to take longer than most people's ovens so just keep an eye on it. :)