Step 1

Place water in a large bowl; sprinkle with yeast. Let stand until foamy, about 5 minutes. Brush another large bowl with oil.

Step 2

In bowl with yeast, whisk sugar, oil, and salt. Stir in flours with a wooden spoon until a sticky dough forms. Transfer to oiled bowl; brush top of dough with oil. Cover bowl with plastic wrap; let stand in a warm spot until dough has doubled in size, about 1 hour.

Step 3

Turn dough out onto a well-floured surface. With floured hands, knead until smooth, about 15 seconds; divide into 2 balls.

Step 4

To freeze 1-pound balls: Set balls on a plate (they should not touch); freeze until firm, about 1 hour. Then freeze in a freezer bag up to 3 months. Thaw overnight in refrigerator.

Step 5

To freeze individual shells: Divide each ball of dough into 4 pieces. Using your hands, stretch each piece into a 5-inch disk (if dough becomes too elastic to work with, let it rest a few minutes).