For the Cake:
Preheat your oven to 350 degrees.
Grease a 9 inch springform pan with butter or baking spray. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment combine the eggs and sugar and beat on high speed until ribbons form, about 15-20 minutes.
Meanwhile in a mixing bowl sift the flour, cornstarch and cocoa powder at least 3 times.
Sift the dry ingredients over the top of the eggs a little bit at a time and fold in very carefully until all the dry ingredients are fully incorporated.
Once all the dry ingredients and folded into the eggs take one full cup of the batter and mix it into the melted butter. Once combined fold the mixture into the remaining batter.
Pour into the prepared pan and bake for 40 minutes or until the center is springy.
Cool completely before glazing.
For the Glaze:
In a mixing bowl whisk together the confectioners sugar, espresso coffee, espresso powder and heavy cream until smooth. You can make the glaze as thin or as thick as you like by adding more or less heavy cream. Drizzle over cake and serve.