1-1/4-ounce package active dry yeast
1-3/4 cups lukewarm water
1 teaspoon sugar
4-1/2 to 5 cups flour
1-1/4 teaspoons salt
3 tablespoons olive oil
2 teaspoons fresh rosemary, chopped
1/4 cup minced onion
1/2 pound Kalamata or green Greek olives, pitted and cut into small pieces
1-1/2 teaspoons coarse salt
In the large bowl of an electric mixer fitted with the dough hook, stir together the yeast, sugar and 1-3/4 cups lukewarm water. Let the mixture set for 5 minutes or until foamy.
Stir in 4-1/2 cups of the flour, salt and 2 tablespoons of the olive oil and knead the dough for 3 minutes, scraping down the dough hook occasionally and adding as much of the remaining 1/2 cup of flour as necessary to form a soft, slightly sticky dough. Transfer the dough to a lightly oiled bowl, turn it to coat it with the oil, and let it rise, covered, in a warm place for 1 hour or until doubled.
Knead in the chopped rosemary; press the dough with lightly oiled hands into a well-oiled pizza pan and let rise, covered loosely, for 30 minutes.
Preheat oven to 400 degrees. Dimple the dough with your fingertips, making 1/4-inch-deep indentations, brush it with the remaining 1 tablespoon oil and top it with the onion, olives and coarse salt.
Bake focaccia in the bottom third of the preheated oven for 35 to 45 minutes or until it is golden. Transfer to a rack and let it cool for 10 minutes, then serve.