Line an 8x8 inch baking dish with plastic wrap. Leave enough overhang of plastic wrap on the sides to make for easy transfer when the cake is ready to serve. Set aside.
Crush Oreos into fine crumbs, reserve 1 cup of cookie crumbs for later. Next, crush up the freeze dried strawberries until they are fine crumbs. Add strawberry crumbs into a bowl with the reserved 1 cup of Oreo crumbs and mix together. In a separate bowl, pour the other 2 and 1/2 cups of crumbs into a bowl and mix in 4 tablespoons of melted butter. Mix until the crumbs are evenly coated with melted butter. Pour crumbs into the baking dish and use your hands to pat them down evenly to form a crust.
Scoop half of the cool whip onto the crust and smooth out evenly. Place the baking dish in the freezer for 15 minutes to firm up.
Meanwhile, make the strawberry sorbet (or use store bought)* : combine frozen strawberries and water (start with 1/2 cup of water, add a little more if needed) into a blender. Blend on high speed until a smooth, thick consistency forms. Remove baking dish from freezer and pour the strawberry mixture over the cool whip layer. Make sure the strawberry layer is smoothed out, return baking dish to the freezer for 15 minutes.
Layer the rest of the cool whip over the strawberry layer and smooth it out. Melt the remaining 4 tablespoons of butter and add it to the reserved cookie crumbs/freeze dried strawberry mixture. Mix together until the crumbs are coated. Evenly sprinkle crumbs all over the top of the cake. Cover with plastic wrap and return to the freezer to freeze for at least 6 hours or up to over night.
When ready to serve to the cake out of the freezer and lift it up by the sides of plastic wrap and let it thaw on the counter for at least 15 to 20 minutes. Cut into squares and serve.