Preheat the oven to 180 ° C. Warm the milk, pour into a bowl and add the yeast broken by hand. Stir and pour in one cup flour and half of the sugar. Mix well, cover the mixture with a towel, set aside for half and hour to rise. In a large bowl, beat three egg yolks well with the remaining sugar and in a large bowl, the vanilla. Add the chopped spoon sweet, orange zest, liqueur and melted butter. Stir the yeast mixture with the egg mixture and add the flour slowly (as much as needed) until the dough is firm and soft.
Cover the dough with a towel and leave it in a warm place to inflate. Once it’s ready, ferment it again and divide it into two equal parts by forming two loaves. Place them in a buttered baking dish, smear their surface with the egg yolk and cut it in the shape of a cross.