I made this recipe from Taste of Home for dinner. The meat is incredibly tender! There's some changes I made to make it easier and vegetable-packed.
First, I didn't bother with sauteing the onions. I just tossed them in with the potatoes. (If you do this, use only two tablespoons of oil instead of four.) Also, I used two white potatoes, one sweet potato and carrots. The sweet potatoes lended a nice sweetness to the whole pie and ups the healthy factor.
And save time and energy by using a premade crust. Just make sure it's MSPI-friendly! If you do decide to make a crust, Crisco's recipe is superb.