"This is a big batter and the cake is very rich. Make sure you have a lot of people around you when you bake it or you will find yourself eating too much of this delicious, but oh-so-sinful cake with that little sting of chile. Serve with vanilla quark curd or vanilla yogurt and some slices of fresh mango."
Place chiles in a bowl with water to cover; let soak until slightly softened, about 15 minutes.
Place 1 1/2 cups dark chocolate and 1 cup plus 2 tablespoons butter in top of a double boiler over simmering water. Stir frequently, scraping down the sides with a rubber spatula to avoid scorching, until chocolate is melted, about 5 minutes. Remove from heat.
Preheat oven to 325 degrees F (165 degrees C). Line a 10-inch springform pan with parchment paper.
Place chiles in a food processor; process until finely chopped. Add almonds, cocoa powder, flour, and cinnamon; process until almonds are chopped. Add Greek yogurt. Mix chile mixture thoroughly into the bowl of melted chocolate to make the batter.
Place egg yolks and egg whites into 2 different bowls. Place 3/4 cup sugar into the bowl of egg yolks; mix until fluffy and creamy. Stir carefully into the batter.
Beat egg whites until foamy using an electric mixer. Add 6 tablespoons sugar gradually, continuing to beat until medium peaks form. Blend meringue carefully into the batter; pour batter into the prepared pan.
Bake until a toothpick inserted into the center comes out mostly clean, 25 to 30 minutes. Let cake cool, at least 20 minutes.
Combine 1 1/2 cups dark chocolate, milk chocolate, and 2 tablespoons butter in a bowl.
Combine 1 cup plus 1 tablespoon heavy cream and 2 tablespoons sugar in a saucepan over medium heat; bring to a boil. Pour over the bowl of chocolate; mix thoroughly. Let ganache cool, at least 15 minutes. Spread over the cake.