Preheat oven to 350F (no fan) and prepare 3 8" pans with parchment paper and butter.

In a bowl, combine the flour, baking powder, baking soda, granulated sugar, light brown sugar and salt. Whisk together until no lumps remain.

In a separate bowl, whisk together the eggs, vegetable oil, buttermilk and sour cream until smooth.

Add the dry ingredients to the wet in 2 additions, and gently whisk and fold until just combined and no big lumps remain. Do not overmix.

In a separate small bowl, add cocoa powder and instant coffee. Pour over boiling water and whisk until a smooth shiny mixture forms.

Pour the cocoa mixture onto the remaining batter, and gently fold until a chocolate cake batter forms.

Divide the batter evenly between the 3 prepared cake pans.

Bake for ~22-24 minutes until a toothpick inserted in the center comes out with light moist crumbs attached.

Let the cakes cool in the pans for 20 minutes, then carefully remove them and place on a wire rack. Let cool completely (refrigerate for 1 hour).

For the frosting, add chocolate and corn syrup to a saucepan and heat over the lowest flame while stirring constantly until the chocolate has fully melted. Set aside.

In the bowl of a stand mixer, add room temperature cream cheese and sift in cocoa powder, powdered sugar and salt. Use the paddle attachment and whisk on medium speed until creamy (1-2 minutes). Scrape the bowl.

Add heavy cream and whisk again on low speed until fluffy. Scrape the bowl in the middle.

Pour in the melted chocolate while whisking on low speed until fully combined into the frosting.

Let the frosting cool until spreadable (at room temperature for ~30 minutes or in the fridge).

Once the cakes and frosting have cooled, use a large serrated knife to carefully trim off the domes from the cakes.

Layer the cakes on top of each other with a generous layer of frosting in between. Cover the cake with a thin layer of frosting (crumb coat) and refrigerate for 20 minutes.

Slather on remaining frosting all over.

Serve & enjoy! Cake is best eaten at room temperature.