Measure your unsalted cold butter with a kitchen scale.
Use a cheese grader to shave your chunks of butter into small pieces.
Place your two separate measurements of cold butter into individual containers to freeze. This makes your pastry process much easier.
Freeze your butter pieces for 45-60 min. before making dough.
Weigh and sift flours into a medium bowl. Whisk together adding in the salt. Place the bowl of flour into the fridge to chill for 30 minutes.
Prepare a bowl of ice cold water and set aside a Tbsp scoop.
Mix the 60 g of cold butter into the flour by hand until resembles cornmeal.
Slowly add your cold water, working in with your hands until a dough is formed.
If dough is too dry add a small bit of water. Dough should not be super sticky.
Wrap dough ball in plastic and chill in fridge for 30 minutes.
Remove dough and roll into a long rectangle about 1/4 inch thick onto floured surfaces.
Sprinkle half of the remaining 200 g of cold butter into 2/3 of the dough.
Grab the remaining uncovered third of dough and fold inward over the middle third.
Then take the thick folded dough and fold over the last butter covered third.
It should now resemble a trifold book.
Take the book and rotate 90 degrees.
Roll back into a flat rectangle.
Sprinkle the last of the cold butter onto 2/3 of the dough.
Repeat the folding process.
Once you have another dough book, rotate 90 degrees again.
Repeat the rolling into a rectangle, and folding into a book 3 more times. (You will not have any more butter, but fold the thirds the same way.
Cover rough puff pastry dough in plastic and place in fridge to chill for 3-4 hrs. before using.