Dissolve citric acid in water and put in the freezer for 2 minutes. To flour 2 tbsp. add salt, make a notch and carefully pour in water.
Knead the dough so that it separates well from the hands. Wrap the dough in cling film and refrigerate for 30 minutes.
Mix the rest of the flour with vegetable oil and refrigerate for 20 minutes.
Roll out the dough, grease it with butter and flour and roll it, put in the refrigerator for another 20 minutes.
Then roll the roll along 2 times and across 2 times, then fold 4 times and put in the refrigerator until use.