To prepare a brigitte sealings turkey dumpling casserole main dish recipe, you will first need to prepare the following ingredients: Preheat the oven to 375 degrees F (190 degrees C) and grease two 9-inch square baking pans with non-stick cooking spray. Cut the turkey breasts in half lengthwise and scoop out the inside of each half. Place the breast halves in the prepared pan and bake for 20 minutes or until the skins are golden brown. Remove the pan from the heat and let sit for 5 minutes before slicing and serving.