Preheat oven to 350°F. Grease the bottom and sides of a 9 inch round pan, set aside.
In a bowl, melt the dark chocolate, semi-sweet chocolate, and butter.
In a large bowl whisk together the separated egg yolks and add the melted chocolate and butter mixture.
In another bowl, whip the egg whites until soft peaks begin to form. While continuing to beat, slowly add sugar and beat until stiff peaks form.
Add ¼ of the beaten egg whites to the egg yolk and chocolate mixture. Fold egg whites in until just combined.
Add another ¼ of the beaten egg whites to the egg yolk and chocolate mixture to lighten the mixture.
Place the remaining ½ of the egg whites on the egg yolk and chocolate mixture.
Sift the flour onto the egg whites and fold into the egg yolk and chocolate mixture until just combined and no egg white streaks are seen.
Pour batter into the prepared 9 inch pan. Bake for 35 to 40 minutes or until the cake is done and the top looks dry. Remove cake from pan and allow to completely cool on a wire rack.
One cake is cooled, carefully cut into 2 even layers with a serrated knife. Evenly spread the lemon curd over the bottom layer. Place the top cake half on top of the lemon curd.
Place the cake on a wire rack over a baking sheet to catch excess glaze. Pour the warm glaze over cake and allow to cool. Serve once glaze has set.