How to cook
Prepare the syrup by putting the water, orange peel and sugar on high heat. As soon as it boils, reduce the heat to moderate, boil for 10 minutes and remove it. Add the drops of rum essence and leave the syrup to cool down, during which time, you can work on the cake mixture.
Beat the eggs, egg whites and sugar, until a white mixture is obtained and add the yogurt and oil at room temperature. While continuously beating, add the semolina, orange peels (it is important that they are very finely grated) and ground hazelnuts.
Finally, sift the flour with the baking powder directly into the mixture and mix, until it becomes homogeneous with a wooden or silicone spatula.
Pour the mixture into a greased and floured baking pan and bake at 370°F (190°C) for 28-30 minutes (the oven must be preheated).
With a toothpick, make numerous holes on the surface of the already baked cake, so that they are not noticeable, while with a fork, for example, they stand out more.
Pour the cold syrup over the hot cake and leave it to absorb it well. You don't have to wait all night or many hours. In 2 hours, the syrup has absorbed well and is ready for consumption.
If you take the cake out of the refrigerator, leave it at room temperature for a while before serving - the aromas are better sensed this way and it is tastier.
Garnish it with cream and a fruit topping of choice.