Step 1
Measure butter & shortening onto a plate put into freezer for about 20 minutes.
Step 2
Measure cake flour all-purpose flour sugar salt and baking powder into the bowl of a food processor. Pulse for a few seconds to mix.
Step 3
Take 1/2 of the cold butter and 1/2 of the cold shortening put into processor with dry ingredients and pulse off and on for about 1 minute. Scrape down twice while doing this.
Step 4
Take remainder of the cold butter & cold shortening and cut in very briefly with the processor leaving visible pea-sized chunks. Do not over process at this stage!
Step 5
In a measuring cup mix egg yolk and vinegar together add ice cubes and water. Let this get chilled about 3 to 4 minutes.
Step 6
Remove mixed flours and shortening from processor put into a large mixing bowl. Sprinkle approximately 4 to 5 tablespoons of this egg water vinegar mixture a little at a time mixing gently with a fork. The key to this is you do not want a wet dough and you do not want to overmix.
Step 7
Place this dough into plastic wrap or plastic bag chill in refrigerator for a few minutes. (May also be frozen for a few weeks at this stage for future use).
Step 8
Remove from refrigerator and roll out. This makes absolutely the BEST pie crusts. I have won County Fair competitions with this pie crust. Double for making a 2-crust pie.