Pork n' Potato Pie ~gluten free

Serves 6 This one is a keeper! Good way to use up leftover roast pork!
2 lbs potatoes
1/3 cup milk
4 tablespoons butter
3/4 teaspoon salt
1/4 teaspoon pepper
1 medium onion, diced
1 teaspoon garlic powder
1/4 cup cornstarch
14 1/2 ounces beef broth (I used leftover gravy from the pork roast)
1 teaspoon mustard powder
1 teaspoon dried thyme
4 tablespoons parsley
2 1/2 cups cooked pork, cubed.
1 can green beans (or one cup cooked)
Preheat oven to 375
Cook potatoes until soft. Drain well and mash with milk and 2 tablespoons butter, salt and pepper
Spread half the mashed potatoes in a greased, shallow 1 1/2 quart baking dish.
In a skillet, saute onion and garlic powder until tender. Mix 1/4 cup cornstarch with 1 cup of the broth.
Gradually stir in broth, mustard powder, thyme and 2 tablespoons parsley. Stir in pork and green beans. Bring to a boil. Simmer 5 minutes or until beans are done.
Pour over potato crust.
Pipe or spoon remaining potatoes over top.
Bake uncovered for 35-40 inutes or until potatoes are lightly browned.
Sprinkle with remaining parsley.