Lay a large tortilla on the bottom of your pie plate. On top of each layer scoop 1/3 of your carton of ice cream on top and spread evenly across the tortilla. Squeeze a W shape of Hot Fudge Topping on top of that.
Top that layer with another tortilla, press down gently. Spoon another 1/3 container of your ice cream. Spread out evenly. Squeeze another W shape of your hot fudge topping followed by your 3rd and last tortilla.
The top layer will contain the last 1/3 of your tub of ice cream, smoothed out all the way to the edges. Squeeze the last bit of hot fudge in dollop forms all the way around the edges of your ice cream pie to make it pretty
Then it's off to the freezer! Freeze for at least an hour, I usually leave it in for 2 hours. When you take it out shake up your can of original whipped topping and make dollops in between the hot fudge dots on top of your ice cream sundae pie. Then a large dollop in the middle.