1. In a mixer bowl with paddle attachment add flour and salt- mix well on low.
2. Continue on low and add butter and mix on low until the mixture looks coarse and crumbly.
3. Add shortening a little at a time.
4. When the mixture is clumpy and holds together when pressed between your fingers add the water and mix until incorporated into dough.
5. Turn the dough out onto a work surface and fold over a few times.
6. Wrap the dough in plastic and chill for at least 2 hours or up to 5 days in the refrigerator.
7. When chilled roll out and use.
8. Dough can be frozen for up to 1 month.