Cook potato in 2 cups boiling water 20 minutes, or until very
tender.  Drain, reserving 1 cup cooking liquid.  Let cooking
liquid cool until very warm (120 to 130 degrees).  Mash potato,
reserving 1 cup.  Combine 1/2 cup flour and yeast in a large bowl;
stir well.  Combine reserved mashed potato, reserved very warm
cooking liquid, and honey; stir into yeast mixture.  Let stand 
10 minutes.

  Place 3 1/2 cups flour and salt in a food processor, or
bowl of mixer, fitted with a dough hook, and pulse 2 to 3 times.
With processor on, add potato-yeast mixture and oil through food
chute; process until dough leaves sides of bowl and forms a ball.
Process 20 additional seconds.  Place dough in a large bowl coated
with cooking spray, turning to coat top.  Cover and let rise
in a warm place (85 degrees), free from drafts, 1 hour or until
doubled in bulk.

  Punch dough down, and turn out onto a lightly floured surface;
knead 2 or 3 times.  With floured hands, divide dough into 2 portions; form
each into a ball (dough will be sticky).  Cover dough; let
rest 15 minutes.  Pat each ball into a 12-14 inch circle on large
baking sheet sprinkled with cornmeal.  Top and bake at 500 degrees
for 8-10 minutes.