1. We will start by placing the rum and raisins in a bowl and let them rest for about 30 minutes. In this way the raisins will hydrate and take on all the flavor.
2. Next, we melt the butter and mix it with the sugar.
3. Add the eggs and mix very well.
4. When they are well integrated, we add the mixture of raisins and rum.
5. Sift the flour and yeast and mix until a homogeneous mixture is obtained.
6. We grease a rectangular mold and pour the dough inside.
7. We take the preheated oven to 170ºC and bake for about 40-45 minutes or until when poking it with a toothpick it comes out clean.
8. Let the cake cool in the pan for 5 minutes and turn it out onto a wire rack to finish cooling completely.
9. Optionally, sprinkle a pinch of icing sugar on top before serving.