01 - Preheat oven to 350°F. Grease a 9x13 inch baking pan thoroughly with cooking spray or butter.
02 - In a large bowl, combine red velvet cake mix, eggs, vegetable oil, buttermilk, and vanilla extract. Mix with electric mixer or whisk until completely smooth and well combined, about 2 minutes.
03 - Pour the cake batter evenly into the prepared baking pan, spreading into an even layer with a spatula.
04 - In a separate bowl, beat softened cream cheese and butter until creamy and smooth, about 2 minutes. Add powdered sugar and vanilla extract, beating until fluffy and well incorporated.
05 - Drop spoonfuls of the cream cheese mixture randomly over the cake batter, leaving some spaces between dollops.
06 - Using a knife or skewer, gently swirl the cream cheese mixture through the batter in a figure-8 or circular motion to create a marbled effect. Do not overmix.
07 - Sprinkle chocolate chips, chopped pecans, and shredded coconut evenly over the entire surface of the batter.
08 - Bake for 38 to 42 minutes, or until the center is mostly set. A few gooey spots are acceptable—do not overbake as the fudgy texture is intentional.
09 - Allow cake to cool in the pan for at least 30 minutes before slicing and serving. Serve warm for extra gooeyness or refrigerate for a firmer texture.