Preheat your oven to the temperature indicated on the white cake mix package. Combine the cake mix with the necessary ingredients according to the box instructions. Pour the batter into a greased 9x13-inch baking pan and bake for the recommended time.

Remove the cake from the oven and allow it to cool in the pan at room temperature for about 30 minutes.

Poke holes evenly across the surface of the cooled cake using the end of a wooden spoon, spaced about 1 inch apart.

In a medium bowl, dissolve the raspberry-flavored gelatin in 2 cups of hot purified water. Pour the mixture over the cake, allowing it to soak into the holes for 10-15 minutes.

Warm the raspberry preserves in the microwave for about 30 seconds. Use a spatula to evenly layer the warm raspberry preserves over the soaked cake.

Spread the thawed whipped topping evenly over the raspberry layer, covering the entire surface of the cake for a smooth finish.

Sprinkle the unsweetened shredded coconut over the whipped topping if desired. Ensure an even distribution.

Cover the cake with plastic wrap or foil and refrigerate for a minimum of 4 hours, preferably overnight, before serving.