Bake the cake in a greased 9x13 pan, according to package directions, until done. Allow the cake to cool completely.
Using the end of a wooden spoon, poke deep holes evenly all over the cake.
Add the peach pie filling and cream to a blender, blending until evenly combined. Pour the mixture evenly out over the cake, making sure to get it in the holes. Spread using the back of a spoon, if necessary, to make sure it gets into the holes.
Spread the whipped topping evenly out over the top of the cake. Sprinkle with nutmeg, and chill for 4 hours.
Slice and serve, as is- or top with a scoop of vanilla ice cream & fresh (or canned) peach slices for a prettier presentation.