Use this recipe when making Mrs. Dunlinson's Plate Cakes.
In the bowl of a food processor, combine flour, salt, and sugar. Add the butter, and process until the mixture resembles coarse meal, 8 to 10 seconds.
With machine running, add 1/4 to 1/2 cup ice water, in a slow, steady stream through the feed tube. Pulse until dough holds together without being wet or sticky; be careful not to process more than 30 seconds. To test, squeeze a small amount together: If it is crumbly, add more ice water, 1 tablespoon at a time. Divide dough into two equal parts. Flatten each ball into a disk; wrap in plastic. Chill at least 1 hour. Dough may be stored, frozen, up to 1 month.