• Preheat the oven to 350°F (175°C). Grease and flour a round cake pan.
• In a mixing bowl, beat the egg yolks with half of the sugar until pale and thick.
• In a separate bowl, beat the egg whites until stiff peaks form, gradually adding the remaining sugar.
• Gently fold the flour into the egg yolk mixture until just combined.
• Carefully fold in the beaten egg whites until fully incorporated.
• Pour the batter into the prepared cake pan and bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.
• Allow the cake to cool completely before removing it from the pan.

For the coconut cream:

• In a saucepan, combine the coconut cream, sugar, and cornstarch. Cook over medium heat, stirring constantly, until thickened.
• In a separate bowl, whisk the egg yolks. Gradually add a spoonful of the hot coconut mixture to the yolks, stirring constantly to temper them.
• Pour the tempered egg yolks into the saucepan with the coconut mixture, stirring continuously.
• Cook for another few minutes until the mixture thickens further.
• Remove from heat and stir in the coconut rum to taste. Allow the coconut cream to cool completely.

For the Swiss meringue:

• In a heatproof bowl, combine the egg whites and sugar.
• Place the bowl over a pot of simmering water, making sure the bottom of the bowl doesn't touch the water.
• Whisk constantly until the sugar has dissolved and the mixture reaches 160°F (71°C).
• Remove the bowl from the heat and beat the mixture with a hand mixer or stand mixer until stiff, glossy peaks form.

For assembly:

• Once the genoise sponge cake has cooled, slice it horizontally into two layers.
• Place one layer of the cake on a serving platter and spread a generous amount of coconut cream on top.
• Place the second layer of cake on top and cover the entire cake with the Swiss meringue.
• Refrigerate the bienmesabe for at least 8 hours before serving to allow the flavors to meld.