Whisk the egg whites and beat on medium speed, after 30 seconds slowly stream in two tablespoons of sugar, then beat until stiff peaks form.
Whip Egg Whites
Melt the chocolate and butter slowly over low-medium heat, stirring frequently- be careful you do not want to burn the chocolate.
Once the chocolate has melted take-off of the heat and stir the remaining sugar, salt, espresso powder, vanilla extract,
and sift the
cocoa powder in.
Add Dry Ingredients
Whisk until smooth, let cool for 5 minutes then whisk in the egg yolks.
Place ½ of the whipped egg whites into and gently fold in. When mostly combined add the second half of egg whites and again gently fold them in, just until no white streaks remain.
Fold Egg Whites
Pour into prepared pan and bake for 28-33 minutes, until the edges are set and the center jiggles only slightly when the cake
is shaken gently.
Cool for 30 minutes on a wire rack then I like to place the cake in the fridge for another 30 minutes to an hour to set up. If you don't it
will be very, very soft.
Let Cake Cool