In a large bowl, stir together 7 cups of flour and salt, making a well in the center. Pour olive oil into the well and add yeast mixture. Stir well with a wooden spoon until it can't be stirred any longer and all ingredients are combined.
Dust work surface when some of the remaining flour. Turn dough out onto the floured surface and knead for about 10 - 12 minutes, adding more flour if necessary, until the dough is smooth and silky to the touch.
Shape dough into a ball. Rub with additional olive oil. Place in a large bowl and cover with a cloth. Let stand for about 2 hours in a warm, draft-free place until doubled in bulk.