Preheat the oven to 375° Fahrenheit. Brush six 4-ounce ramekins with melted butter. In a small bowl, whisk the cocoa powder with 1 tablespoon of the flour; dust the ramekins with the cocoa mixture, tapping out the excess. Transfer the ramekins to a baking sheet and set aside.

In a medium bowl over a pot of simmering water, melt 1 stick of butter with the chocolate, stirring occasionally until fully melted, about 5 minutes. Remove from heat and allow mixture to cool slightly.

In a bowl of an electric mixer fitted with the whisk attachment, beat the granulated sugar, eggs, egg yolks, and salt over high speed until very thick and pale yellow, about 3-4 minutes. Add the vanilla extract. Remove bowl from mixer and using a rubber spatula, fold in the melted chocolate until no streaks remain. Gently fold in the flour until mostly incorporated. Be sure not to over mix.

Fill the the prepared ramekins slightly less than halfway. Nestle 4 cherries in the center and pour cake batter over the cherries. Do not fill the jars to the rim; otherwise the cake will spill over when it begins to rise.

Bake cakes in the center of the oven for 10-14 minutes, until the tops are cracked but the centers are still slightly jiggly. Transfer the ramekins to a rack and let cool for about 5 minutes.

Run the tip of a small knife around each cake to loosen. Invert a small plate over each cake and, using pot holders, or a clean dishtowel, invert again. very carefully lift off the ramekins.

Garnish with more cherries and a sprinkle of confectioners' sugar, if desired.