1. Dissolve the yeast in the lukewarm water for about
10 minutes, until foamy.
2. Pour the flour onto a clean, dry surface, making a well in
the center. Gradually pour the dissolved yeast into the well,
adding 1/3 of the sugar and the salt. Mix with a wooden spoon
until all the liquid is incorporated into the flour. Knead into
a smooth, elastic dough.
3. Form the dough into a ball; place in a lightly oiled bowl
and cover with plastic wrap. Leave dough to rise in a warm place
for about 2 hours, until doubled in bulk.
4. Brush a half-sized sheet pan with olive oil. Remove the dough
from the bowl and punch down. Roll the dough out some; place it
on the pan and form it onto the pan with your hands. Poke with
the fingers to achive a surface of hills and valleys. Vover with
the nuts and grapes; sprinkle with the remaining sugar. Cover
with plastic wrap and let rise about 30 minutes more.
5. Preheat the oven to 400° F and bake for 40 minutes, until
golden. Remove from the pan and cool.