In a small bowl, add the water, sour cream, and vinegar. Whisk to combine, and place in the fridge while you continue to work.
To the bowl of a food processor, add the flour, sugar and salt. Process to combine well.
Add the frozen butter to the food processor. Process until the flour resembles pea sized chunks and grated parmesan cheese.
Add the mixture of water, sour cream, and vinegar, and process until the dough forms large chunks but still isn't a solid mass.
Turn the dough out onto a piece of plastic wrap.
Using your hands, divide dough in half, and form into two rounds.
Refrigerate until ready to roll and use.