1/2cup (8 tablespoons) unsalted butter, plus 2 tablespoons more for greasing pans
3/4cup granulated sugar
3 large eggs
1 teaspoon vanilla extract
1cup all-purpose flour
2 tablespoons of high quality Dutch process cocoa powder
1/2 teaspoon baking powder
4ounces bittersweet chocolate, chopped
1/4 teaspoon kosher salt
9oz semisweet chocolate
2 tablespoons dried rose petals
sea salt, for sprinkling
Instructions
Preheat oven to 360°F and position an oven rack in the middle of the oven.
Melt 2 tablespoons of butter in a small saucepan and generously brush the madeleine wells with butter. Place the pan in the freezer. Once butter has hardened, after a few minutes repeat the process with another layer of butter and leave the pan in the freezer to chill until ready to use.
In a stand mixer fitted with a paddle attachment, beat the 8 tablespoons of butter and sugar until light and fluffy, about three minutes. Add the eggs, one at a time, mixing until each egg is fully incorporated before adding another. Add the vanilla and salt and mix until combined.
In a medium bowl, sift the flour, cocoa and baking powder together. Add the flour mixture to the egg mixture with the mixer on low speed, add flour mixture in 3 additions, mixing just until all the flour is incorporated.
Melt the chopped chocolate in a double boiler and let it cool slightly. Fold the melted chocolate into the batter by hand just until incorporated.
Remove the buttered pan from the freezer and spoon enough batter into each shell until each shell is filled, smooth the tops. Place the filled mold back into the freezer until batter is chilled, about 15 minutes. Bake cookies for 12 to 15 minutes until risen and just set.
Remove from oven and flip cookies out onto a wire rack to cool.
To make the ganache, melt chocolate in a double boiler over medium low heat. Dip each madeleine halfway into the chocolate, then set back on the wire rack. Sprinkle with dried rose petals and salt, then allow chocolate to harden completely.