Prepare cake mix according to directions and pour into a 9x13 pan and bake.
While cake is baking, prepare strawberry dessert topping. In a medium saucepan, add strawberries, sugar and lemon juice. Cook until thickened., about 6 minutes. It will take longer to thicken if using frozen fruit. Once the topping coats the back of a spoon, pour into a heat proof bowl and set aside.
Once the cake is baked, remove from the oven and let cool for about 15 minutes.
Prepare the Jello and put into a jar that is easy to pour from.
Slice the strawberries for the top of the cake.
Once the cake is cooled enough to touch comfortably-warm, but not hot, poke holes in the cake so the Jello has a place to go. I used the handle of a wooden spoon and poked in fairly even lines all the way up the cake. Once the holes are poked, you pour the prepared Jello over the cake evenly.
Then, spread the strawberry dessert topping evenly over the cake.
Top the cake with the cool whip and the sliced strawberries. Place in the refrigerator for 3 hours so everything has a chance to set.
Notes
Add Food Coloring: Make the whipped topping a pretty red color by adding food coloring.
Make Icing: No cool whip, try using a light icing.
Variation tip: Use vanilla pudding in place of the Jello for a more creamy flavor.
Poke Holes: If you do not have a wooden spoon with a round handle use a straw.