Preheat oven to 350. Spray a 9x13 glass baking dish with cooking spray. 

Mix together the pouch of Sugar Cookie Mix, 1/2 cup softened butter, 1 tsp vanilla extract and the egg.  If your butter is soft enough you should be able to do this by hand with a wooden spoon!

Evenly spread the cookie dough on the bottom of your prepared 9x13. I find this easiest to do if you break the dough into little pieces and scatter into your baking dish.  Then use a spatula (or your fingers!)  and press the dough evenly.

Bake at 350 for 18-20 minutes or until lightly golden. Let cool completely.

In a microwave safe bowl, carefully melt your white chocolate. This should take about 1 minute depending on your microwave.

In a separate bowl beat your cream cheese and vanilla extract. Add your melted white chocolate and beat until smooth.  Evenly spread over your cooled cookie layer and refrigerate while you make the strawberry layer.

In a small saucepan crush 1 cup of your strawberries (leave the remaining 3 cups sliced). Add the 1/2 cup sugar. Stir the cornstarch into the water making sure there are no lumps. Add to the saucepan of crushed strawberries and bring to a boil over medium heat stirring frequently until thickened. Remove from heat and let cool for about 5 minutes.

Carefully stir in the the 3 cups of sliced, fresh strawberries until all coated.  Immediately pour over the cream layer and spread with a spatula.  Cover with plastic wrap and return to the fridge for another hour. Serve same day!