In a medium bowl, add the flour and salt. Mix together.
Cut the butter into cubes and add it to the flour. Using a pastry blender or two knives, cut the butter into the dough until the butter is in pieces the size of peas. The dough will be quite crumbly.
Make a hole in the center of the dough and pour in all of the water. Stir to combine the dough.
Add the dough to a floured surface and pat it into a rough square. You will still be able to see pieces of butter and the dough may seem quite dry but it will come together with each roll.
Flour the rolling pin, and roll the dough out into a rectangle about 25-30cm long.
Fold the bottom third of the dough over the middle of the dough. Fold the upper third of the dough on top of the middle too. Rotate the dough one-quarter turn, roll out again, and repeat the folding pattern. Use flour as needed to stop the dough from sticking.
Roll out, fold, and turn the dough at least 6 or 7 times.
When done, wrap the dough in plastic wrap and chill for at least one hour, or overnight. At this point you may freeze the dough.
Roll out with flour when you are ready to use the pastry.
1. To make sure the water is icy cold, measure ⅓ cup of water into a 1 cup measure. Top it up with ice cubes, stir it around and pour out ⅓ cup of now icy cold water