Preheat oven to 350°F (175°C) and grease your cake pan.
In a bowl, whisk together flour, cocoa powder, baking powder, baking soda, and coffee granules.
In another bowl, beat together sugar, butter, and eggs.
Add buttermilk and vanilla extract, mixing until smooth.
Gradually add the dry ingredients to the wet ingredients, stirring until just combined.
Make the Cream Cheese Filling
In a separate bowl, beat cream cheese, sugar, egg, and vanilla extract until smooth and creamy.