01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan thoroughly with cooking spray or butter.
02 - In a large bowl, combine strawberry cake mix, eggs, vegetable oil, and water. Beat according to package directions until smooth, approximately 2 minutes. Pour batter evenly into the prepared pan.
03 - In a separate bowl, beat softened cream cheese and butter together until creamy. Add powdered sugar and vanilla extract, continuing to beat until smooth and lump-free, about 2-3 minutes.
04 - Drop spoonfuls of the cream cheese mixture evenly across the surface of the cake batter, leaving some spaces between dollops.
05 - Scatter the diced fresh strawberries and white chocolate chips over the top of the batter and cream cheese mixture. Sprinkle shredded coconut evenly across the surface if desired.
06 - Using a butter knife, gently swirl the cream cheese mixture into the cake batter in a circular or figure-eight motion. Do not overmix—the goal is a marbled appearance with distinct layers visible.
07 - Bake for 40-45 minutes until the edges are set but the center remains slightly gooey. The cake should not be completely firm in the middle when tested with a toothpick.
08 - Allow the cake to cool in the pan for at least 30 minutes before slicing. Serve warm or at room temperature for the best texture and flavor.