For the mashed potatoes:
Put the peeled and cut potatoes into a pot and cover with cold water by 2-3 inches then add 2 tablespoons salt and bring to a boil. Cook the potatoes until soft. (do not overcook as they will become mushy.) Drain the cooked potatoes and return them to the empty pot. For each pound of potatoes and ¼ cup Freund’s garlic butter and mash with a hand potato masher. Once the potatoes are mashed then season to taste with salt and black pepper. Set aside to completely cool.
To Assemble and Cook Pot Pie:
Wash and dry the salmon cubes, then place them inside a large bowl. Defrost the peas and carrots under cold running water, drain and add them to the salmon. Add the chopped onion. Season with ½ tablespoon pepper, 2 tablespoons of Freund’s house seasoning and ½ cup of Freund’s garlic butter and mix well.
Preheat oven to 350°.
Take a suitable sized oven-proof casserole dish and gently create a crust on all sides and the bottom from the mashed potatoes (no more than ¼ inch thick). Pour the salmon and vegetable mixture inside the crust and use the remaining mashed potatoes to form a crust over the top. Cover and bake 40 minutes.
After 40 minutes remove from the oven and take off the cover, then return to the oven for an additional 15 minutes, or until the top turns a golden brown.
Once the top has browned remove from oven and let cool for 20-25 minutes before serving.