Here is the recipe, by special request! Enjoy!
Preheat oven to 350 degrees.
Butter cake pan completely and then line bottom with parchment paper. Butter parchment paper. Dust pan with flour or cocoa powder. I use unsweetened dutch cocoa powder. Shake off excess.
Place a heat proof bowl over simmering water and add:
3 1/2 ounces unsweetened chocolate, coarsely chopped
4 ounces semisweet chocolate, coarsely chopped( I used Ghiradelli chocolate for both)
15 tablespoons (2 sticks minus 1 tablespoon) unsalted butter
Heat until melted and smooth, stirring often. Set aside to cool.
Seperate 6 eggs
Whisk the 6 yolks with 1/2 cup of sugar until all sugar has dissolved
Fold yolk mixture into melted chocolate
In seperate bowl, whisk 6 egg whites until foamy
Gradually add 1/2 cup sugar, 1/4 teaspoon salt
Whisk until mixture is glossy and holds a shape, this takes some minutes
Fold whites into chocolate mixture in 3 parts. Fold only until no white streaks appear.
Pour batter into cake pan, smooth the top and bake for 35 to 40 minutes. (35 works for me)
The cake will develop cracks on top, this is normal. Cake is done when sides are set and center is slightly soft.
Let cake cool completely. Invert cake onto plate and remove parchment paper.
The recipe calls to invert the cake again. I, however, do not invert it again and sprinkle with powdered sugar. Stencils work great with the powdered sugar!
I will say here you definitely need a glass of cold milk or yummy vanilla ice cream standing by!