01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan thoroughly with cooking spray or butter.
02 - In a large bowl, combine the strawberry cake mix, eggs, vegetable oil, and water. Beat with electric mixer on medium speed for 2 minutes until completely smooth. Pour batter evenly into the prepared pan, spreading to corners.
03 - In a separate medium bowl, beat together the softened cream cheese and butter until fluffy. Add powdered sugar and vanilla extract, continue beating until completely smooth and creamy, about 2-3 minutes.
04 - Drop tablespoon-sized portions of the cream cheese mixture evenly over the cake batter, spacing them across the entire surface.
05 - Scatter the chopped fresh strawberries and white chocolate chips evenly over the top. Sprinkle shredded coconut across the surface if using.
06 - Using a butter knife or skewer, gently swirl through the layers in a figure-8 or zigzag pattern to marble the cream cheese, cake batter, and toppings together. Work lightly to avoid overmixing—the batter should remain distinctly swirled, not blended.
07 - Bake for 40-45 minutes until the center is just set and a toothpick inserted into the thickest part comes out with a few moist crumbs attached. The top should be golden brown with slightly cracked edges.
08 - Allow the cake to cool completely in the pan, at least 1-2 hours. The center will settle as it cools. Slice into 12 squares and serve at room temperature or chilled.