Preheat oven to 350.
Line a 12"x17" baking sheet with parchment paper and lightly spray with non-stick cooking spray, set aside.
In stand mixer beat your butter and sugar until light and fluffy.
Add in your eggs, one mixing well after each addition, then add in your vanilla until combined,.
In large bowl, whisk together flour, jello and baking soda.
Alternate adding your dry ingredients and your milk until combined.
Lastly fold in your diced strawberries.
Spread into prepared pan and bake for 22-25 minutes or until slightly golden on top, remove from oven and cool completely.
To make your frosting in stand mixer add your cream cheese and butter and beat until creamy.
Add in your powdered sugar one cup at a time until combined.
Lastly add in your strawberry puree, if mixture is too runny add a little more powdered sugar.
Spread over cooled cake and serve.