Easy Chocolate Loaf Cake

Preheat the oven to 325 degrees F. Line a 9-by-5-inch loaf pan with parchment paper and set aside.
In a large mixing bowl, whisk together the cake flour, cornstarch, sugar, baking powder, baking soda, and kosher salt. Set aside.
In a separate large bowl, add sour cream and oil. Mix together until combined, then add the eggs and vanilla extract. Continue to mix until everything is fully incorporated, about 30 seconds, then add in the cocoa powder and mix until combined.
Add flour mixture to the wet ingredients. Mix until just combined, then pour hot coffee and mix together until a loose batter forms, about 15 seconds.
Pour the batter into the prepared pan and bake for 55-65 minutes, until a toothpick comes out of the center of the loaf with just a few crumbs and just slightly coated in the batter. Let the loaf sit in the pan for 15 minutes, then remove onto a wire rack to cool completely.
When the loaf has cooled completely, prepare the chocolate ganache topping by adding heavy cream to microwave safe bowl. Warm for one minute, then add the semi-sweet chocolate chips. Mix together until the chocolate melts into the cream (microwave in 10 second increments if the chocolate doesn't melt completely but be careful not to burn the chocolate!), then add butter and mix until fully melted and smooth.
Pour the ganache on top of the chocolate cake while it's still on the wire rack to prevent making a huge mess.