Mix flour, sugar and salt.
Add cold butter pieces and knead. (Best using a food processor.)
Add ice water and knead for a very short moment.
Divide dough in two and wrap in cling film.
Place in fridge for 1 hour.
The butter and water should be very cold.
The dough should stay cold, that is why it is best to use a food processor to knead.
Knead the dough shortly, so it stays buttery and flaky.
For the ice water I use a small bowl with water and ice cubes. Out of this I take the 6 tablespoons of ice water.