Instructions:

1. Prepare the yeast starter: in a small bowl, mix 1 dl (3.4 fl oz) of milk with a teaspoon of sugar and the yeast. Add enough flour to create a cream-like consistency, similar to sour cream. Let this mixture sit for at least 20 minutes to activate the yeas.

2. In a separate bowl, beat the soft butter or margarine with the powdered sugar until fluffy.

3. Add the room-temperature egg yolks, lemon zest, and vanilla sugar, and mix well.

4. Once combined, add the yeast starter and one-third of the flour.

5. Gradually add the remaining flour and the milk in portions, mixing well until the dough becomes smooth and shiny. It should be soft and a little sticky, which is normal.

6. Add the raisins.

7. Stir in the soaked raisins at the end.

8. Grease a bundt pan (or similar) with melted butter or margarine.

9. Once the fat firms up a little, dust the pan with flour.

10. Let the dough rise: place the dough in the pan and cover it. Let it rise for about 1 hour or until it fills the pan.

11. Preheat the oven to 180°C (350°F) and bake the kuglóf for about 40-45 minutes, or until a toothpick comes out clean.

12. Once baked, remove the bundt cake from the pan and let it cool completely.

13. Sprinkle with vanilla powdered sugar before serving.