Perfect Pastry

In large bowl, whisk together flour and salt ; using pastry blender or 2 knives, cut in cubed butter and shortening until mixture resembles fine crumbs. In 1-cup (250 mL) liquid measure, whisk egg yolk with vinegar; add enough ice water to make 1/3 cup (75 mL).

Gradually sprinkle egg mixture over flour mixture, stirring briskly with fork until pastry holds together and adding a little more water if necessary. Press into disc; wrap in plastic wrap. Refrigerate until chilled, about 30 minutes. (Make-ahead: Refrigerate for up to 3 days or freeze for up to 1 month.)