01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan thoroughly.
02 - Whisk strawberry cake mix, eggs, vegetable oil, and water in a large bowl until just combined. Pour batter evenly into prepared pan.
03 - Beat cream cheese and butter until smooth. Add powdered sugar and vanilla extract; beat until creamy and fluffy.
04 - Drop spoonfuls of cream cheese mixture randomly over cake batter.
05 - Sprinkle diced strawberries and white chocolate chips evenly over top. Add shredded coconut if using.
06 - Use a butter knife to gently swirl cream cheese mixture through batter for marbled effect.
07 - Bake for 40 to 45 minutes until edges are set and center is slightly wobbly. Do not overbake; cake should remain gooey inside.
08 - Cool in pan for at least 30 minutes before slicing and serving.