Schiacciata all'uva

It seems like fall has finally made it to Florence: the days are shorter, it's no longer above 30 degrees every day, and the nights are pleasantly cool. And of course, there's the food. Porcini have reappeared, the first cavolo nero has been sighted, and the summer stone fruit has largely given way to pears and grapes. With the last of these, particularly the small wine grapes, you can make an excellent Italian/Tuscan treat -- Schiacciata all'uva.

• 25g equivalent dried yeast (one packet)
  
• 350g (~2 3/4 cup) flour
• 4 tbsp olive oil
• 100g (~1/2 cup) sugar (can be more if desired)
  
• salt

To garnish:

• 1kg (~2 1/4 lbs) black (wine) grapes -- the ones they have here are small, sweet, and have a large seed-to-flesh ratio
• sugar
• olive oil
• rosemary

Dissolve the yeast in a little lukewarm water and add to the flour, oil, two tbsp. sugar and a pinch of salt in a large bowl. Knead together with additional water as needed, form into a round ball, cover the bowl and leave to rise in a warm place for about two hours. Carefully remove grapes from their stalks, wash and leave to dry.
Divide the dough in two and roll out into rectangles the same size as the baking tray you are using. Put one piece in the greased tray and top with half of the grapes. Sprinkle with a little sugar and put the second rectangle of dough on top. Cover with the remaining grapes and the remaining sugar. Drizzle with oil and rosemary. Bake at 180° C (350°) for about 40 minutes.

(from Sandra Rosi: Florence, The Art of Cookery)