Gluten Free Cheesy Chicken and Mashed Potato Casserole

We had this for dinner tonight and it is very yummy.  It has dairy in it because we have added dairy back into our diet.  However, I will give suggestions on making this dairy free if it is necessary.  This could also be called Chicken Shepherds' Pie.

Gluten Free Cheesy Chicken and Mashed Potato Casserole
Serves 6

In a medium sized frying pan over medium-high heat, cook about 5 minutes or till translucent

1 tablespoon butter
2 tablespoons olive oil
1 medium sized onion, 1/2" dice
4 medium sized mushrooms, halved and sliced thin
1/4 teaspoon sea salt
1/4 teaspoon lemon pepper

Set this mixture aside to cool.

In a mixing bowl combine

1 cup sour cream (or goat's milk yogurt)
1/2 cup unsweetened applesauce
2 tablespoons ground flaxseed
1 cup chicken broth (watch out for commercial broths -- be sure and read labels)
1/2 teaspoon thyme flakes
1 teaspoon sea salt
3 cups chicken, cut up into bite sized pieces

Add the reserved mushrooms and onions with their juices.  Pour this mixture into an 8"x13"x2" baking pan and smooth it out.  Cover it with

4 slices Swiss cheese, broken up OR about 1 cup shredded Swiss cheese

Combine

6 cups mashed potatoes, well seasoned
1/2 cup sour cream (or goat's milk yogurt)

Use this mixture to top the casserole.  Drop dollops of potatoes across the top of the chicken and cheese filling.  Use about 2/3 of it before beginning to spread it evenly with the back of a spoon.  Continue adding the potatoes until the top is evenly covered and smooth.  Sprinkle the top with

1 1/2 teaspoons parsley flakes

Bake the casserole at 350F for about 30 minutes.  Enjoy!