Preheat your oven to 350°F (180°C) or 160°C if using a fan oven. Grease a 9x13 inch (approximately 23x33 cm) baking pan well.
Scatter the shredded coconut evenly at the bottom of the greased pan, followed by the chopped toasted pecans. Make it as even as possible so there’s coconut and pecan in every bite.
In a large bowl, mix together the Devil's Food Cake Mix, water, vegetable oil, and eggs according to the package instructions. Pour the cake batter evenly over the coconut and pecan layers in the pan.
In a separate bowl, using a hand mixer, beat the cream cheese and butter. Then add in the powdered sugar, salt, and vanilla extract and mix until smooth.
Dollop spoonfuls of the cream cheese frosting over the cake batter (I use a cookie scoop, but you can use a spoon), staying about 1 inch away from the edges to prevent it from oozing out of the pan. Use a knife or spatula to gently swirl the frosting into the cake batter, creating a marbled effect.
Place the pan in the preheated oven and bake for 40 minutes, or until a toothpick inserted in the center comes out mostly clean.
Let the cake cool slightly and then serve warm, or allow it to cool completely to get neat slices.