Sift flour and salt into a large chilled metal bowl.
Using a vegetable grater coarsely grate frozen butter into flour, tossing to coat butter in flour.
Add 5 tablespoons ice water over flour mixture and stir with a fork until incorporated.
Pick up a small handful and squeeze. The mixture will hold together when ready. If still crumbly add more water and retest.
Refrain from overworking mixture or adding too much water as it will cause pastry to become tough.
Layout a sheet of baking paper and push the mixture together to form a 20sm square, wrap in cling film and chill for 30mins. (It will look really rough)
Remove dough from the fridge and roll out on a floured surface till you have a 40cm x 20cm rectangle.
Starting with the with a short side nearest you fold the dough into thirds, bottom edge to middle third, top edge over bottom fold.
Rewrap dough and chill for another 30 minutes.
Continue to roll out and fold dough 2 more times.
Then wrap dough in cling film and chill at least 1 hour.
Ready to use in a great pastry creation.