In a measuring jar, mix the beaten eggs, milk and water together.

Mix the flour, yeast, sugar and zest together in a large mixing bowl. Attach the dough hook of the hand mixer, add the wet mixture into the dry ingredients and mix it at low speed. Then turn to medium speed to beat it until well combined, the dough should be smooth and elastic. It takes about 8 minutes with hand mixer. Place the dough onto floured worktop, shape it into a ball, then put in plastic bag and chill in fridge for 1 hour.

Take out the dough and put on floured worktop, roll out into 35 x 20 cm rectangle.

Put the whole block of butter between two parchment paper, roll into 20 x 15cm rectangle. Then put the butter on top of the dough.

Fold one side of the dough over the butter, then top with the remaining butter side, like an envelope. Seal the sides to prevent the butter come out. Put it in a plastic bag and chill in fridge for 1 hour. 

Take the dough out and place on floured worktop with the long end towards you. Roll it out into rectangle about 35 x 20 cm, fold one-third of the dough, then fold the top third down on top. Put it back to the plastic bag and chill in fridge for 1 hour.

Repeat this stage for twice more, and chill the dough in fridge in between. After the last time, chill the dough overnight. Cut the dough into three pieces, Wrap it separately with plastic bag and freeze it. Take out the dough from freezer and place in fridge the night before you use it.