Puff pastry dough is one of those things in the kitchen that is incredibly versatile and can be used in so many ways. Its not hard, just a little practice.
Add the cold water and mix to a rough dough. Wrap it and place in the fridge. Leave to rest for about 30 minutes.
While you are waiting, take the unsalted butter and soften a little on the counter. Place a large piece of waxed paper or parchment paper on the counter about 12"X6". Chop the butter into 3 piece rectangles. Place them on the paper side by side, then place another piece of the paper of your choice on top.
With your rolling pin roll the butter out to an 8" flat rectangle. Still in the paper place the butter slab in the fridge.
When the dough is finished resting, knead the dough by pushing it away with the heals of your hands, then folding it back over, give it a quarter turn and start from the beginning. Continue until the dough is smooth and elastic.
Roll it out until it is big enough to wrap around the butter slab. Place the butter in the center of the dough and fold the edges over, so the butter is completely hidden.
Turn this dough butter sandwich over onto a lightly floured board and begin rolling it out to a rectangle shape. This begins the lamination process. Fold the rectangle into thirds and roll out again into a rectangle. Fold into thirds one more time and place in the fridge again for 30 minutes
Repeat the above another three times and rest the dough in the refrigerator until you need to use it.
Basicallyrolling the pastry will distribute the butter throughout it. The butter must be softened just enough to allow you to roll it in the dough. If taken out of the refrigerator for a short time before using it will be just right. Let the creativity begin!
Notes
It is important not to let your dough become too warm, so the butter remains in little pockets not completely incorporated into the flour.