Originally cooked in the ashes of the hearth, schiacciata, 
which mean "squashed," is usually about an inch thick.  
Variations of the bread are made throughout Italy; Tuscans 
simply brush it with olive oil and sprinkle it with salt.  
Sometime they add herb or make a sweet version with grapes 
and sugar.  Remember that bread doughs can have different 
consistencies depending on the climate:  This one should 
be soft, but not too sticky.  Add more flour if it feels 
to wet.

Make one round loaf

1 cup lukewarm water (90 F to 100 F)
2 1/4 ounce packages dry yeast or two 0.6 ounce packages 
      fresh yeast, crumbled
2 1/2 cups (about) all purpose flour
4 tablespoon extra-virgin olive oil
1 tablespoon coarse sea salt

Pour 1 cup lukewarm water into small bowl; sprinkle with yeast.  
Let stand until yeast dissolves, about 10 minutes.

Place 2 cups flour in large bowl.  Make well in center of flour.  
Pour yeast mixture into well.  Using fork, stir until dough comes
together.  Knead in bowl, adding enough flour 1/4 cup at a time 
to form slightly sticky dough.  Transfer to floured work surface.
Knead until dough is smooth and elastic, about 10 minutes.  
Coat bowl with 1 tablespoon oil.  Add dough; turn to 
coat.  Cover bowl with plastic wrap.  Let stand in warm 
draft-free area until doubled, about 1 hour 15 minutes.

Brush 11-inch-diameter tart pan with removable bottom or baking 
sheet with 1 tablespoon oil.  Punch down dough.  Turn out onto 
floured work surface and shape into 11-inch round.  Transfer 
dough to prepared tart pan or baking sheet.  Cover loosely with
plastic.  Let rise until dough is almost doubled, about 30 
minutes.

Pre heat oven to 400 F.  Press fingertips into dough, creating
indentations.  Brush with remaining 2 tablespoon oil.  Sprinkle 
with salt.  Bake until golden, about 28 minutes.  Cool bread 
in pan on rack 10 minutes.  Remove bread from pan; cool 
completely