Mix 250g brown sugar, 160ml buttermilk, 160ml vegetable oil, 120g yogurt, 2 eggs, and 1 tsp vanilla together
In a separate bowl, combine 280g all-purpose flour, 1 tsp baking powder, 2 tsp baking soda, and ½ tsp salt
Mix 250ml hot water with 1 tbsp instant coffee and 50g cocoa powder
Combine wet and dry ingredients, then add the coffee mixture
Pour batter into a 13"x10" tray and bake for 30-35 minutes
For the chocolate cremeux: heat 120ml milk and 120ml whipping cream together
Pour hot cream mixture over 200g chopped dark chocolate and let sit for 1 minute, then whisk until smooth
Whisk 2 eggs + 1 yolk with 25g sugar until pale
Temper the eggs by slowly adding the chocolate mixture while whisking constantly
For the cream cheese filling: beat 250g cream cheese until smooth
Mix in 15g cocoa powder and 30g powdered sugar
Whip 120ml whipping cream to stiff peaks and fold into cream cheese mixture
Once cake is cooled, slice into two layers
Cut cake into 4"x8" loaf pan sizes
Layer the cake with chocolate cremeux and cream cheese filling
