1. In a mixing bowl, combine 50ml of the lukewarm milk with 15g of the yeast and 3g sugar 2. Combine 50g flour and whisk until fully combined 3. Cover and allow to rise at room temperature for an hour 4. In a smaller mixing bowl, melt the remaining 3g of yeast in 10ml of lukewarm milk and add to the risen mix 5. Add 100g of the sugar and 1 beaten egg to the risen mix 6. Transfer 200g of the remaining flour in a large mixing bowl and make a well in the centre of it 7. Gradually pour in the risen mix and knead 8. Add 30g of the butter and knead until fully combined 9. Cover the dough and allow to rise for another hour 10. Knead in the remaining flour, egg, salt and vanilla 11. Flatten the dough, fold and allow to rise again until it has doubled in size 12. Chill the dough for 12 hours 13. Roll out the dough in a square shape and spread 140g of butter onto its centre 14. Fold the corners of the dough towards the centre 15. Roll out into a rectangle and fold in three 16. Chill for 20 minutes and repeat the folding another two times 17. Roll out the dough and shape into a ball 18. Place the dough into a cylinder mold and allow to proof at room temperature for an hour 19. Set the oven at 160°C on combi 20. Bake for an hour, dust with icing sugar and serve