Make a block of butter and dough separately. To prepare the butter block, mix 400 g butter in 175 g flour using a low-speed mixer. Transfer to plastic, give a square shape (15 cm) and leave in the refrigerator for 2 hours. For the flour block you will need: 185 ml of cold water, 1 g of salt, 1/2 teaspoon of vinegar, 420 g of flour and 100 g of thick chilled oil. Mix flour and oil first, then add water, salt and vinegar. Give a square shape (10 cm) and store in the refrigerator for 2 hours. After 2 hours, spread a piece of butter on a table sprinkled with flour, put a block of flour on one side, and form on the other. Fold up to 1 cm in thickness so that it is three times longer than in width. Return to the refrigerator for 20 minutes, then flatten and fold again. Repeat this action twice. Then roll the dough to 3 mm thick and cut into slices. Beat with a fork and bake at 200 degrees for 20 minutes. When working with the dough, as soon as we feel that it is softened, put it back in the refrigerator.