Brown the ground beef in a skillet, Add the green enchilada, black olives and mushrooms to the ground beef and simmer until the sauce is bubbly.
Crush the Frito's into small pieces and layer half of the bag at the bottom of a pan (I used a glass pan) Pour the meat mixture on top of the layer of chips.
Spread the rest of the chips on top of the meat mixture and sprinkle the cheese on top. Bake the pie in the oven on 400 degrees until cheese is melted. Cut the "pie" into 8 squares and place a dollup of sour cream on top of each square. Enjoy!