1Preheat oven to 350 degrees F (175 degrees C). Spray the inside bottom of a jelly roll pan with cooking spray.
2Mix sugar cookie mix, butter, and egg together in a large bowl until a soft dough forms; press evenly into prepared pan.
3Bake in the preheated oven until crust is light golden brown, 10 to 15 minutes. Cool completely, about 30 minutes.
4Beat cream cheese using an electric mixer on medium speed in a bowl until smooth. Add whipped topping and stir until smooth; spread over crust. Refrigerate.
5Mix sugar and cornstarch together in a 2-quart saucepan; add 1 cup strawberries, water, and vanilla extract. Cook and stir strawberry mixture, mashing strawberries with spoon while cooking, over medium heat until strawberries are softened and mixture is thickened, 10 to 15 minutes.
6Stir food coloring into strawberry mixture and remove from heat; cool for 10 minutes. Gently stir remaining 3 cups strawberries into strawberry mixture; spoon over cream cheese filling. Refrigerate until set, about 1 hour. Serve within 4 hours.