Add 2 cups of water and 1 cup ice to a medium bowl. Set aside.
Add the flour and the salt to a large food processor.
Remove the butter cubes from the freezer, add to the food processor and put on the lid.
Pulse about 20 times until a course meal is formed with pea sized chunks of butter remaining.
Measure out 100 grams of water from the bowl of ice water.
Turn the food processor onto the dough setting (continuous) and slowly add the water in a steady stream to the running food processor.
Continue to let the food processor run until the dough comes together into a ball on one side of the food processor
Place 1 tbsp of flour on a clean, cool work surface and spread out into an even layer.
Turn out the dough onto the floured work surface and quickly knead the 2 tbsp flour into the dough.
Set the dough aside, place another 1 tbsp flour on the work surface, and roll out to 1/4 inch thickness.
Spread 4 tbsp softened butter in a thin layer all over the top of the dough sheet using an offset spatula or the back of a spoon.
Trim the jagged edges off the dough so that it makes a symmetrical rectangle.
Fold the dough in half length wise. Spread 2 tbsp butter into a thin layer on top.
Then fold the dough into thirds (letter style).
Wrap the dough tightly in plastic wrap and place flat in the refrigerator.
Chill for 1 hour.
Place 1 Tbsp flour on a clean work surface and spread into a thin layer.
Remove the dough from the refrigerator, unwrap, and place on the floured surface.
Roll out to a thickness of 1/4 inch.
Use and bake the rough pastry according to your recipes directions. For 2 inch by 2 inch puff pastry squares I recommend brushing the top with cream or an egg wash and baking at 375 degrees for 25-27 minutes. Make sure the pastry dough sheet are VERY cold prior to baking so you may need to place them back into the refrigerator for up to 20 minutes prior to baking.