Preheat your oven to 350°F (175°C) and grease the 9x13-inch baking pan.

In a large mixing bowl, combine the chocolate cake mix, water, vegetable oil, and eggs. Mix with an electric mixer on medium speed until well combined, about 2 minutes.

In another bowl, beat the softened cream cheese until smooth. Mix in the powdered sugar and vanilla extract until fully combined and creamy.

Pour half of the chocolate cake batter into the prepared baking pan, spreading it evenly.

Scoop dollops of the cream cheese mixture over the cake batter. Use a knife or spatula to swirl it into the batter gently.

Sprinkle the chopped strawberries on top of the cream cheese layer. If using coconut or nuts, sprinkle them over the strawberries.

Pour the remaining chocolate cake batter over the top and smooth it out.

Bake in the preheated oven for 45 minutes, or until a toothpick inserted into the center comes out clean.

Allow the cake to cool in the pan for at least 15 minutes before slicing and serving.

For added flavor, drizzle chocolate ganache or whipped cream over the cake before serving.

This cake is best enjoyed the same day but can be stored in an airtight container in the refrigerator for up to 3 days.