Begin making the chocolate cake: Spray to coat a standard bundt pan with nonstick cooking spray. Coat with ¼ cup unsweetened cocoa powder. Shake out the excess and set aside.
In a large bowl, whisk to combine the all-purpose flour, remaining ¾ cup cocoa powder, granulated sugar, espresso powder, kosher salt, baking soda, and baking powder.
Add the eggs, vegetable oil, and buttermilk. Whisk until smooth.
Whisk in ¾ cup hot water to combine. Set the batter aside.
Make the cheesecake filling: In a separate, medium-sized bowl, beat the cream cheese and sugar until smooth.
Add the egg, vanilla, flour, and salt. Beat to combine.
Pour two-thirds of the chocolate batter into the prepared bundt pan.
Use a 2-ounce scoop or spoon to portion the cheesecake batter evenly into the center of the batter, avoiding the edges of the pan.
Top evenly with the remaining chocolate batter (the cheesecake batter will float).
Bake for 55 to 60 minutes, until the cake springs back to the touch and a wooden pick inserted in the center comes out with only moist crumbs and no wet batter.
Let cool in the pan on a wire rack for 1 hour.
Flip onto the rack or a serving plate and chill until cold, at least 2 hours.
Heat the heavy cream in a small pot to a simmer.
Turn off the heat. Add the chocolate chips, salt, and vegetable oil.
Whisk until smooth.
Immediately drizzle the chocolate evenly over the top of the chilled cake. Top with chocolate shavings, if desired.