Separate the egg yolks and the white.
Mix the flour with the baking powder and the poppy seeds.
Beat the egg yolks with the sugar to a creamy mass.
Add the olive oil, fresh cheese, milk and rum essence to the dough, while beating constantly.
Add the flour and mix the dough until it is one creamy mass.
Beat the eggwhite until stiff, and mix carefully under the dough.
Grease a baking tray of 30x40 cm.
Pour the dough in the baking tray and spread it evenly.
Bake in a preheatet oven at 180°C during 30 minutes.
Remove the cake from the oven and let it cool down.
For the icing, melt the butter and add the lemon juice and the icing sugar.
Mix until the sugar has diluted completely.
Spread the icing over the cake and let it cool down.