Put first 3 ingredients in large bowl and mix well with fork.
Add shortening and mix with fork until crumbly.
In small bowl, beat together with fork 1/2 cup water, the vinegar and the egg.
Combine the two mixtures, stirring with a fork until all ingredients are moistened.
Divide dough into 4 or 5 pieces and shape each portion into a flat round patty. Wrap each patty with plastic wrap and refrigerate for at least 1/2 hour.
When ready to roll piecrusts, lightly flour each side of patty and the rolling pin. Roll out on a floured surface or between 2 pieces of waxed paper or parchment paper. Roll to thickness of 1/8 inch and 2 inches larger than pan.